Monday

May 30, 2016
Total # Posts: 34,826

**Math**

prob(good) = .9 prob(bad) = .1 you want prob(6 of 7 to be good) = C(7,6)(.9)^6 (.1) = .. you push the buttons
*March 5, 2016*

**Math**

value of $1.00 at end of 1 year: Bank A : amount = (1 +.0479/12)^12 = ... Bank B : amount = (1 + .048/4)^4 = .. compare the results
*March 5, 2016*

**Algebra**

are we solving √(8-3x) + √(6x-1) = 7 - 2√(9x-24) ???? I tested it in Wolfram, and there is no "real" solution, so I won't even try. http://www.wolframalpha.com/input/?i=%E2%88%9A(8-3x)+%2B+%E2%88%9A(6x-1)+%3D+7+-+2%E2%88%9A(9x-24) notice that ...
*March 5, 2016*

**math**

factors of 1440 2x720 3x480 4x360 5x288 6x240 8x180 9x160 10x144 12x120 15x96 16x90 18x80 20x72 24x60 30x48 32x45 36x40 ---> that's all of them values of n^2-1 1,3,8,15,24,35,48,63,80,99,120,143,168,195,288,325,360,399,440,483,529,575,624,675,728 the largest of these ...
*March 5, 2016*

**math**

values of n+1 2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,.... multiples of 4n+1 5,9,13,17,21,25,29,33,37,41,45,49,53,57,61,65,69,73,77,81,85,89,93,97,101,... let 4n+1) = k(n+1) k = (4n+1)/(n+1) , so k has to be whole number if n=2 , 9/3 = 3 --> k = 3 if n=3, 13/4 ≠ ...
*March 5, 2016*

**Algebra**

speed of slower --- x km/h speed of faster ---- x+2 km/h 20/x - 20/(x+2) = 20/60 = 1/3 times 3x(x+2) , the LCD 60(x+2) - 60x = x(x+2) x^2 + 2x - 120 = 0 (x+12)(x-10) = 0 x = 10 or x = -12, the ladder is silly The slower one went 10 km/h, and the faster went 12 km/h check: 20/...
*March 5, 2016*

**Math**

width --- x length --- (6/5)x (6/5)x^2 = 480 x^2 = 400 x = √400 = 20 picture is 20 inches by 24 inches
*March 5, 2016*

**business math**

Did you mean simple interest? if so, PRT = I 52600(.05)T = 1261 T = 1261/(.05(52600)) = .4795 years or 175 days check: 52600(.05)(175/365) = 1260.96 or $1261
*March 5, 2016*

**Calc Derivatives**

you should say y = (4x-3)/(3x^(1/2)) or f(x) = (4x-3)/(3x^(1/2)) dy/dx =[ 3x^(1/2) (4) - (4x-3)(3/2)x^(-1/2) ]/(9x) = 0 for a max/min 12x^(1/2) = (3/2)(4x-3)/x^(1/2) 12x = (3/2)(4x - 3) 24x = 12x - 9 12x=-9 x = -3/4 , but x ≥0 or else x^(1/2) is undefined. There are no ...
*March 5, 2016*

**math ples help**

using these log rules: log(ab) = loga + logb log(a/b) = loga - logb log( a^n) = nloga Rewrite 2log8/6 + 2^2log3 - 2log12 as log(64/36) + 4log3 - log144 = log(64/36) + log81 - log144 = log ( (64/36)(81)/144) = log 1 = 0
*March 5, 2016*

**Math**

The simple proportion for your similar triangles: h/48 = 5/12 12h = 240 h = 20 or by straight logic: The mirror is 4 times the distance away from the pole as she is from the mirror. So the flage pole is 4 times her height, or 20 ft " Find the geometric mean of the pair of...
*March 5, 2016*

**math**

Ok ... RS = sinx/√(1+cosx) * √(1-cosx)/√(1-cosx) , you did that = sinx √(1-cosx) /(√( (1+cox)(1-cosx) ) = sinx √(1-cosx)/√(1 - cos^2 x) = sinx √(1-cosx)/√sin^2 x = sinx √(1-cosx)/sinx = √(1-cosx) = LS
*March 5, 2016*

**math**

solve for m, the number of miles .09m + 57.98 = .14m + 49.98 9m + 5798 = 14m + 4998 ...
*March 5, 2016*

**Math**

Make a Venn diagram Label it P and B, for pepperoni and banana put 5 in the intersection of both circles - of the 25 who like pepperoni, 5 are already counted, so put 20 in the P circle apart from the intersection. - of the 31 who like banana peppers, 5 are already counted, so...
*March 5, 2016*

**Maxima, Stationary Points**

If (9*x^6+28*x^4+51*x^2-88*x-10)/(3*x^2+2)^2 is the derivative of some function and you want to find max/min, you would set the above equal to zero that would leave you with 9x^6 + 28x^4 + 51x^2 - 88x - 10 = 0 I am not at all familiar with your software, but my favourite math ...
*March 5, 2016*

**math**

How good are you at sketching 3-D diagrams? I let P be the point directly below plane A, and I now have 4 triangles, each in their own plane. Redraw each with a side view: right-triangle ABP , right angle at P right-triangle ACP, right angle at P triangle BCP , (on ocean floor...
*March 5, 2016*

**trigonometry**

sinx/secx = 1/tanx+cotx , is not true but sinx/secx = 1/(tanx+cotx) is true LS = sinx(1/cosx) =sinxcosx RS = 1/(sinx/cosx + cosx/sinx) = 1/( (sin^2 x + cos^2 x)/(sinxcosx) ) = 1/(1/sinxcosx)) = sinxcosx = LS
*March 5, 2016*

**college algebra**

let the three numbers be x x+2 x+4 2x - (x+2) = 20 x = 22 largest is x+4 = 26
*March 5, 2016*

**MATH**

Make a sketch, (it won't be to scale!) You will have an isosceles triangle with an angle at the earth of 31 minutes of angle. Draw in a perpendicular which would be 360,000 km If the radius of the moon is r, I see it as tan (0°15'30") = r/360000 r = 360000(tan...
*March 5, 2016*

**Math**

let the two numbers be 3x and 4x 3x+10 = 4x - 10 solve for x
*March 5, 2016*

**Allgebra**

let the two numbers be x and y (x+y)/2 = 17 x+y = 34 --> y = 34-x √(xy) = 8 xy=64 x(34-x) = 64 x^2 - 34x = -64 x^2 - 34x + 289 = 289-64 ---> I completed the square (x-17)^2 = 225 x-17 = ±15 x = 32 or x = 2 if x = 32, y = 2 if x = 2, y = 32 , (called ...
*March 5, 2016*

**Algebra**

in a harmonic progression, the reciprocals of its terms form an arithmetic progression. so if the third term of the HP is x then 1/a , 1/b, and 1/x form an AP that is, 1/b - 1/a = 1/x - 1/b 2/b - 1/a = 1/x (2a - b)/(ab) = 1/x x = ab/(2a - b)
*March 5, 2016*

**Algebra**

"one third of a one third of a point is deducted" - why not just say say: " 1/9 of a point is deducted for an incorrecte answer" ?? number correct --- x number incorrect --- 72-x x - (1/9)(72-x) ≥ 60 x - 8 + (1/9)x ≥ 60 (10/9)x ≥ 68 x &#...
*March 4, 2016*

**maths**

1/x + 1/(x+6) = 1/(40/3) = 3/40 times 40x(x+6) 40(x+6) + 40x = 3x(x+6) 3x^2 - 62x - 240 = 0 t = (62 ± √6724)/6 = 24 or -3/1/3 , but x > 0 so x = 24 tom alone can do it in 24 hrs, John alone can do it in 30 hours check: at combined time, time of job = 1/(1/24+1/...
*March 4, 2016*

**probability**

prob(zero people leave tip) = C(6,0)(.7)^0 (.3)^6 = .000729 prob(1 person leaves tip) = C(6,1)(.7)(.3)^5 = .010206 prob(2 persons leave tip) = C(6,2)(.7)^2 (.3)^4 = .059535 prob(3 persons leave tip) = C(6,3)(.7)^3 (.3)^3 = .18522 prob(4 people leave tip) = C(6,4)(.7)^4 (.3)^2...
*March 4, 2016*

**Calculus with Analytical Geometry**

you are looking for the vertex of h = -16t^2 + 1000t + 20 the t of the vertex is -1000/-32 = 31.25 seconds for that value of t, h = 15645 ft
*March 4, 2016*

**Math Algebra Intermediate**

ay - a^6 y^6 = ay(1 - a^5 y^5) Much Ado About Nothing, as Shakespeare would say.
*March 4, 2016*

**Math**

i = .042/12 = .0035 n = 30(12) = 360 PV =.8(260000) = 208,000 let the payment be P P( 1 - 1.0035^-360)/.0035 = 208000 P = $1017.16
*March 4, 2016*

**Math**

S(1) = 2 by the formula: S(1) = 1(1 + 3)/2 = 2 S(2) = 2+5 = 7 by the formula: S(2) = 2(1+6)/2 = 7 S(3) = 2+5+8 = 15 by formula: S(3) = 3(1+9)/2 = 15 seems to work.
*March 4, 2016*

**math**

let the two numbers be x and x+1 4x + x(x+1) = 36 x^2 + 5x - 36 = 0 (x+9)(x-4) = 0 x = 4 or x = -9, but x>0 x = 4 the two numbers are 4 and 5
*March 4, 2016*

**Algebra 2**

(log5 16^3 )(log11 6^2 = log x 3(log16/log5)(2)(log6/log11) = logx 6(log16/log5)(log6/log11) 6(1.28724...) = logx 7.72346... x = 10^7.72346.. x = appr 52,900,679 I was using the log properties: log a^n = n loga , and log a b = logb/loga
*March 4, 2016*

**algebra 1b**

typo: don't know where my 20 came from. should have been: quarters ---- x nickels ----- 16-x solve for x: 25x + 5(16-x) = 220
*March 4, 2016*

**algebra 1b**

quarters ---- x nickels ----- 20-x solve for x: 25x + 5(20-x) = 220
*March 4, 2016*

**math**

let the total be x make a Venn diagram of two intersecting circles, and place 27 in the intersection. In the exclusive parts of the two circles place (3/4)x - 27 and (4/7)x - 27 then: (3/4)x-27 + 27 + (4/7)x-27 = x (3/4)x + (4/7)x-27 = x multiply each term by 28, the LCD 21x...
*March 4, 2016*

**Math**

Was that supposed to say KL = 14 ? I will assume that, since N does not enter the picture elsewhere. Let's find angle K, the largest angle. 18^2 = 14^2 + 16^2 - 2(14)(16)cosK 448cosK = 128 cosK = 2/7 K = appr 73.4° area = (1/2)(14)(16)sinK = 112(.9583..) = appr 107.33 ...
*March 3, 2016*

**Geometry**

in any rhombus, the diagonals right-bisect each other. illustration: midpoint of PR = (0,0) midpoint of QS = (0,1/2) oops, something is not right the figure is not a rhombus, I think S should be (1,-2) then midpoint of QS is also (0,0) and the two diagonals would bisect each ...
*March 3, 2016*

**typo at end - statistics**

Last line of previous post should have been: number of ways = 4x36 = 144
*March 3, 2016*

**statistics**

a) consider each couple as one unit, so you are just arranging 3 units. Number of ways = 3! = 6 b) I don't understand the question c) for the men to sit together, we could have MMMWWW **** WMMMWW WWMMMW WWWMMM Number of ways to do *** = 3x2x1x3x2x1=36 but each of the other...
*March 3, 2016*

**Calculus Related Rates**

let the distance between them be x ft after a time of t seconds, distance of the northbound person = 4t ft distance of the other person = 5t ft They walk at an angle of 45° to each other. By the cosine law: x^2 = (4t)^2 + (5t)^2 - 2(4t)(5t)cos45 = 41t^2 - 40t^2 (√2/2...
*March 3, 2016*

**Algebra**

so you have an arithmetic series with a = 30,000 , d = 2300 sum(10) = (10/2)(60000 + 9(2300) ) = 403,500
*March 3, 2016*

**mathematics**

The way you typed it, all is good, the expression would be real and defined for all values of x but... if you meant: 5x+4÷√(8-4x) , then we have two concerns 1. to be real, 8-4x ≥ 0 -4x ≥ -8 x ≤ 2 2. to be defined: 8-4x ≠ 0 -4 ≠ -8 x...
*March 3, 2016*

**Math**

speed on first part ---- x km/h speed on return trip -- x+2 km/h time on first trip = 42/x time on 2nd trip = 42/(x+2) 42/x - 42/(x+2) =1/2 multiply each term by 2x(x+2) 84(x+2) - 84x = x(x+2) 84x + 168 - 84x = x^2 + 2x x^2 + 2x - 168 = 0 (x-12)(x+14)=0 x = 12 or x =-14, let&#...
*March 3, 2016*

**Mathematics**

Please don't post the same problem again under a different name. Once will do. I just did this for you
*March 3, 2016*

**Maths**

In my diagram, I have the perpendicular from T go PC meeting PC at S, giving me 2 right angled triangles. In triangle CST: tan30° = 6/CS CS = 6/tan30 in triangle PST: tan40° = 6/SP SP = 6/tan40 PC = CS+SP = .... you do the button-pushing
*March 3, 2016*

**Finance**

I am not familiar with US mortgage laws. What is this "3.5% closing cost" ? so is the original mortgage: add 3.5% to 225,000, then take 90% of that? That would be 225,000(1.035)(.9) = $209,587.50 confirm that before I proceed
*March 3, 2016*

**Math**

(-1,14), (0,10), (1,8), (2,?), (3,10), (4,?) and (5,20) the missing values should be like: (-1,14), (0,10), (1,8), (2,8), (3,10), (4,14?) and (5,20) Now if you put those same x value into the straight line you get: (-1,6), (0,7), (1,8), (2,9), (3,10), (4,11), and (5,12) Notice...
*March 3, 2016*

**math**

Join A and B to O, the centre of the circle So we have triangle ABO with all 3 sides known. We can use the cosine law to find angle Ø 6^2 = 9^2+9^2-2(9)(9)cosO 162cosØ = 126 cosØ = 126/162 = 7/9 Ø = 38.94...° (I stored it in calculator's ...
*March 3, 2016*

**Algebra**

amount = 6300(1.06)^3 = 7503.40 how did you get your answer ??
*March 2, 2016*

**trigonometry (Course and Bearing)**

According to my sketch: tan46°10' = 7/AP AP = 7/ tan46°10' = .... sin46°10' = 7/BP BP = 7/sin46°10' = ....
*March 2, 2016*

**Trig**

Of course I can't see where your Ø is let's assume it is opposite the smallest side. 10^2 = 17^2 + 20^2 - 2(17)(20)cosØ 680cosØ = 589 cosØ = 589/680 Ø = appr 29.98° If otherwise, make the necessary changes
*March 2, 2016*

**Math**

1/2 ÷ 1/8 =
*March 2, 2016*

**Math**

be more specific please
*March 2, 2016*

**Algebra**

ummh, notice that two of the terms has a single decimal place with that decimal being an even number What happens when you multiply any even number by 5 ?
*March 2, 2016*

**finance**

PV = 3000(.96) + 3000(.96)^2 or PV = 3000(1/04)^-1 + 3000(1.04)^-2 depending on how "annual discount rate" is defined in your course. btw, they yield different results.
*March 2, 2016*

**Algebra**

pop(chessville) = 50,000(1.07)^n pop(checkerville) = 70,000(.96)^n we want to know when 50,000(1.07)^n ≥ 70,000(.96)^n divide by 10,000 5(1.07)^n = 7(.96)^n take logs of both sides and use rules of logs log5 + nlog1.07 = log7 + nlog.96 nlog1.07 - nlog.96 = log7 - log5 n(...
*March 2, 2016*

**precalculus**

Make a reasonable sketch. Using vectors and using R to be the resultant vector: R = (180cos300,180sin300) + (50cos245,50sin245) = (90,-90√3) + (-21.1309.. , -45.31538..) = (68.869.., -201.1996...) Magnitude = √(68.869^2 + (-201.1996..)^2) = appr 212.66 km direction...
*March 2, 2016*

**MATH.**

done yesterday http://www.jiskha.com/display.cgi?id=1456884647
*March 2, 2016*

**math**

6x^3 + 3x^2 - 9x what about it ?
*March 1, 2016*

**Math**

so number = a e^(kt) 10,000 = a e^(3k) 40,000 = a e^(5k) divide the 2nd by the 1st: 4 = e^(2k) 2k = ln4 k = (ln4)/2 so N = a e^( (ln4)/2 t) so we need a a e^(3ln4/2) = 10,000 a = 10,000/8 = 1250 initial count is 1250 bacteria
*March 1, 2016*

**math**

what is 6000(1.02)^28 ?
*March 1, 2016*

**Math**

time the dog wants to go outside in that time frame = (7/12)(60) = 35 minutes so not wanting to outside = 25 minutes percentage of time not going out = 25/60 = appr 42%
*March 1, 2016*

**Math**

prob = 6/10 = 3/5 a cube has 6 sides, so division by 6 would be the model for probs, we need a division by 5 or 10 or 15 ,etc
*March 1, 2016*

**Pre-Calc**

did you test the answer in the first equation? It clearly works in the last two equations.
*March 1, 2016*

**Algebra**

speed of second train ---- x mph speed of first train --- 2x-10 mph When they meet they would have traveled the same time let that time be t hrs distance gone by first train = tx distance gone by 2nd train = t(2x-1) tx + t(2x-1) = 220 tx + 2tx - t = 220 t(3x-1)=220 t = 220/(3x...
*March 1, 2016*

**Calculus**

I have seen this question, where we have to find the other sides so that the perimeter is a minimum, but ... The way it is worded... there is an infinite number of possible lengths. e.g if the side along the x-axis is 5, then the equation of the line passing through (1,1) has ...
*March 1, 2016*

**math**

f∘g(x)= f(g(x)) = f(4-x^2) = 4(4-x^2) - 3 simplify do the 2nd one in the same way
*March 1, 2016*

**Math**

Did you mean f(x) = √(x+1) ?? I will assume that. f∘g = f(g(x)) = f(3x-5) = √((3x-5) - 5) = √(3x - 10) domain: 3x-10≥0 3x≥10 x ≥ 10/3 ( I will let you switch this to "interval notation, I like the "old way" better) g&#...
*March 1, 2016*

**algebra**

first condition: XX2 XX3 XX5 XX7 Second condition: hundreds is twice tens 842 632 422 212 843 .... ... 847................217 There will be 16 of those I will leave it up to you to decide how many of those are prime numbers. (remember, just because a number ends in an odd ...
*March 1, 2016*

**math**

Just a simple case of tan38 = h/6.6 h = 6.6tan38° = ....
*March 1, 2016*

**math**

amount of 30% solution --- x gal amount of 14% stuff ------ 60-x solve for x .30x + .14(60-x) = .20(60) or if you want two variables: x+y = 60 .30x + .14y = .20(60)
*March 1, 2016*

**math plz help i cant understand this. :'(**

Did you plot the points? Look like a trapezoid. AB is a horizontal line, so that AB = 6 AC and BC are parallel So area = (1/2(AC + BC)(AB) = (1/2)(4+6)(6) = 30 square units
*March 1, 2016*

**math :D**

Easiest to check would be the median We have an even number of data values, so the median is the average of the two middle numbers. so (23+25)/2 = 24, that rules out #1 and #2 the mode is clearly 25 so we have to find the mean: add them up and divide by 8 to see what you get
*March 1, 2016*

**@ Mary - Calculus**

Mary, what part of yesterdays solution did you not like ? http://www.jiskha.com/display.cgi?id=1456770767 Always check to see if your question has been answered before reposting the same thing. That way we avoid unnecessary duplication of work.
*March 1, 2016*

**mathematics**

so 75% would be 45 .75x = 45 x = 45/.75 = ...
*March 1, 2016*

**math**

distance = 4.9t^2, when t=1 distance = 4.9 m
*March 1, 2016*

**math**

This webpage is perfectly suited for your type of problem http://davidmlane.com/hyperstat/z_table.html Just enter the data
*February 29, 2016*

**Calculus**

I would assume you are using the cosine law. let the distance between the two tips be x x^2 = 4 + 9 -2(2)(3)cosØ x^2 = 13 - 12cosØ 2x dx/dt = 12sinØ dØ/dt given: dØ/dt = .5 , Ø = π/4 for Ø = π/4 x^2 = 13 - 12cosπ/...
*February 29, 2016*

**Math**

equation of tangent: y - 5/3 = (-5/9)(x - 5) y = (-5/9)x + 25/9 + 5/3 y = (-5/9)x + 40/9 check my arithmetic
*February 29, 2016*

**math**

Did you make a sketch? On mine I let the top of the tree be A and its bottom be B look at triangle APB. angle ABP = 120° , AP = 4√3, BP = 4 by the sine law: sinA/4 = sin120/4√3 sinA = 4(√3/2)/(4√3) = .5 A = 30° so angle APB = 180-120-30 = 30°
*February 29, 2016*

**math**

Make a little diagram of what actually happens. After the first bounce, the ball goes up and down 2/3 of it previous bounce, but the first event can be considered only half a bounce. so I am going to consider this to be a geometric series, pretending the first bounce is ...
*February 29, 2016*

**math**

I see 2 similar triangles. let length of Christa's shadow be x ft let length of Glad's shadow be y ft so 5/x = 6/y 6x = 5y we also know x+y = 15 or y = 15-x sub into the first: 6x = 5(15-x) 6x = 75-5x 11x = 75 x = 75/11 ft = appr 6.82 ft y = 15-75/11 = 90/11 ft = appr ...
*February 29, 2016*

**math**

just use the formula PV = 1000(1.05)^-8 = ...
*February 29, 2016*

**math**

I will assume this is "simple interest" let the rate be r, let the principal be p so (15/12)(rp) = 455 rp = 364 for only 10 months interest = (10/12)(rp) refund = 455 - (10/12)(rp) = 455 - (5/6)(364) = $151.67
*February 28, 2016*

**geometry**

Ladder is 12 feet out and 16 ft up, A VERY UNSAFE WAY TO PUT THE LADDER!! length of ladder --- L L^2 = 12^2+16^2 = 400 L= √400 = 20 new position: base = 14 , height = ? , L = 20 solve: h^2 + 14^2 = 20^2
*February 28, 2016*

**math**

Good grief, haven't seen that type of question in about 50 years. didn't know they still used it . I will describe the method and then attempt to explain what happened. They are using the word "normal" to mean perpendicular. e.g. in your equation, 2x+3y - 5...
*February 28, 2016*

**math**

sinx < -√3/2 consider sinx = -√3/2 by the CAST rule and knowing that sin 30° = +√3/2 x = 210° or x = 330° also, you should know the general shape of the sine curve. from the above the curve would be below -√3/2 between 210° and 330&...
*February 28, 2016*

**Geometry**

recall that sin^2 Ø + cos^2 Ø = 1 so sin^2 Ø + 9/64= 1 sin^2Ø = 55/64 sinØ = √55/8 then cscØ = 8/√55 or 8√55/55
*February 28, 2016*

**Pre-Calculus**

Important info at the end: "with equal amounts invested in short- and intermediate-term bonds. " So let each of those amounts be x then the amount invested at long-term be 100,000 - 2x He wants to end up with a 5.1% profit on the total 100,000 or $5100 Now it is easy...
*February 28, 2016*

**Algebra**

I will assume you made a diagram. On my diagram, I have each of the long sides as y, and each of the 3 shorter sides as x so we have 3x + 2y = 440 y = (440 - 3x)/2 = 220 - (3/2)x area = xy = x(220 - (3/2)x) = 220x - (3/2)x^2 from the subject title, I assume you don't take ...
*February 28, 2016*

**math**

those solutions where 0 ≤ x ≤ 2π 2cos^2x-5cosx+2=0 this is a standard quadratic where your variable is cosx How about doing this ? let t = cosx then we have 2t^2 - 5t + 2 = 0 , which factors to (2t - 1)(t - 2) = 0 t = 1/2 or t = 2 so cosx = 1/2 or cosx = 2 ...
*February 28, 2016*

**maths**

I can't see any other way than listing the possible cases and finding the total score for each case. Using the first letter of each outcome, we could have BBBB -- 36 BBBS -- 34 BBBT -- 31 BBBO -- 28 BBSS -- 32 BBTT -- 26 BBOO -- 20 BBST -- 29 BBSO -- BBTO etc, watch for ...
*February 28, 2016*

**math**

hard to get the spacing correct, I will use ** for spacing 3|2**0**-1**0***7****1 ******6**18**51*153*480 ***2**6**17**51*160*481 f(3) = 481
*February 28, 2016*

**Math**

prob(hit) = .42 prob(no hit ) = 1 - .42 = .58 at least 2 hits out of 4 ---> exclude : no hits, 1 hit prob(no hits) = C(4,0)(.42)^0 (.58)^4 = .113165 prob(1hit) = C(4,1)(.42)(.58)^3 = .32779 prob(at least 2 hits) = 1 - (.113165 + .32779) = appr .559 or you could do prob(...
*February 28, 2016*

**math**

Tell me what you got, then we'll both be happy
*February 28, 2016*

**math**

This is almost the same kind of question that I answered for you here : http://www.jiskha.com/display.cgi?id=1456693077 Did you look at it, and learn from it? I will give you one hint for this one: cos (2Ø) = cos^2 Ø - sin^2 Ø let me know how you made out.
*February 28, 2016*

**math**

remember cos^2 Ø + sin^2 Ø = 1 .36 + sin^2 Ø = 1 sin^2 Ø = .64 sinØ = .8 sin 2Ø = 2sinØcosØ = 2(.8)(.6) = .96 2Ø = sin^-1 (.96) or arcsin(.96)
*February 28, 2016*

**Geometry/Algebra**

welcome!
*February 28, 2016*

**Geometry/Algebra**

Make a sketch of a right-angled triangle ABC with angleB = 90° Draw in the altitude from C to hypotenuse AC to meet it at D. You now have 3 similar right-angled triangles. (easy to see by considering the angles) I will list them, with corresponding vertices in the same ...
*February 28, 2016*

**Math**

Why could you not check them?? is (1/8)% of 32 = .04 ?? (1/800)(32 = 32/800 = .04 , so YES x(1.8) = 3 x = 3/1.8 = 1.6666.. or 166.66..% or 166 2/3% check that: take 166.66..% of 1.8 = (166.666../100 )(1.8) = 3
*February 28, 2016*

**math**

a+d = 50 a + 4d=65 subtract them 3d = 15 d = 5 then a+5=50 a=45 term40 = a + 39d = 45 + 39(5) = 240
*February 28, 2016*