Branches of Math
Recent Math Questions
The math grades on the final exam varied greatly. Using the scores below, how many scores were within one standard deviation of the mean? How many scores were within two standard deviations of the mean? 99 34 86 57 73 85 91 93 46 96 88 79 68 85 89
Tuesday, December 9, 2014 at 1:07am
Math (Word Problem into formula)
A chemist is studying the properties of a bronze alloy (mixture) of copper and tin. She begins with 6 kg of an alloy that is one sixth tin. Keeping the amount of copper constant, she adds small amounts of tin to the alloy. Letting x be the total amount of tin added, define c(x...
Monday, December 8, 2014 at 11:53pm
An experiment consists of drawing one ball from a box containing 5 white balls numbered 1 through 5 and black balls numbered 6 through 10. Find the probability that a randomly selected ball is black and numbered 7.
Monday, December 8, 2014 at 10:40pm
(6/x^2+5x+6) + (9/x+3) express answer in reduced form What i attempted is to factor out the bottom half of the first fraction to 6/(x+2)(x+3) the second half i'm guessing would be to multiply each side by the x+3? making it a (6x+18/(x+2)(x+3)) + 9 or would i write it as 6...
Monday, December 8, 2014 at 9:53pm
A scale drawing of your classroom is 4 inches by 6 inches. If one inch represents 8 feet, what is the actual size of your classroom? I think I know the answer, jst having trouble figuring out how to write it down & show it. I think it's 32 feet by 48 feet. Help! Thanks
Monday, December 8, 2014 at 8:29pm
On an airplane, there are two seats on the left side in each row and three seats on the right side. There are 90 seats on the right side of the plane. How many seats are on the left side of the plane? How many seats are there altogether?
Monday, December 8, 2014 at 7:54pm
1. 77 is what percent of 192? A. x/100=77/192;4.01%**** B. x/100=77/192;40.1% C. x/77=100/192;77.3% D. x/100=192/77;249.4% 2.Of the 80 eigth-graders, 32 are going on the class retreat. What percnt of the eigth grade going on the retreat? A. 25% B. 55% C. 40% D. 32%*** 3. ...
Monday, December 8, 2014 at 7:48pm
Carrie and Krystal are taking a road trip from Greenville and North Valley . On Carries's map, Greenville and North Valley are 4.5 inches apart. The scale is 1 inch=20 miles. How far is Greenville from North Valley? The scale on Kystal's map is 1=18 miles. How far ...
Monday, December 8, 2014 at 7:47pm
Tom buys a shirt for $22.00 plus 7% sales tax. His cousin buys a shirt for $18.00 plus 4% sales tax. a. How much do Tom and his cousin pay for the shirts? Show your work b. Who spent more on tax My answers $22.00*7%=1.54 $22.00+1.54=$23.54 $18.00*4%=0.72 $18.00+0.72=$18.72 Tom...
Monday, December 8, 2014 at 7:37pm
Forks:Spoons There are 7 forks and 5 spoons. What's the ratio? Explain what the ratio means. I know what the ratio is its 7:5 right? I just need help on the second one. How do I explain it?
Monday, December 8, 2014 at 7:11pm
what x 12 is close to 57 12 divided by 5.79 = That is what I am trying to figure out so i skipped 5 and move on to 57 in the problem and i need to know what x 12 = close to 57
Monday, December 8, 2014 at 6:59pm
5th grade math
Q. The Johnson family has been very busy and has not done there laundry for several weeks. The dirty laundry pile consists 540 items of clothing. They figure they can put average of 27 pieces of clothing in a single load. How many loads if laundry will the Johnson family have ...
Monday, December 8, 2014 at 6:57pm
Let S be the part of the sphere x^2 + y^2 + z^2 = 25 that lies above the plane z = 4. Let S have constant density k. (a) Find the center of mass. (b) Find the moment of inertia about the z-axis. so far I have found that the magnitude of r(theta)x r(thi)= 25sin(thi)but I cant ...
Monday, December 8, 2014 at 6:50pm
Let S be the part of the sphere x^2 + y^2 + z^2 = 25 that lies above the plane z = 4. Let S have constant density k. (a) Find the center of mass. (b) Find the moment of inertia about the z-axis.
Monday, December 8, 2014 at 6:45pm
The population of town A increases from 1,346 to 1,500. In the same period, the population of town B increases from 1,546 to 1,800. a. Find the percent of increase in population for town A and for town B. b. Which town had the greater percent of increase? My answer town A. 1,...
Monday, December 8, 2014 at 6:28pm
1.Of the 80 eith-graders, 32 are going on the class retreat. What percent of the eith grade going on the retreat? A. 25% B. 55%*** C. 40% D. 32% 2.What is the sale price for a pair of shows that was originally prices at $54.99 and now is 20% off? A. $38.49 B. $41.24 C. $43.99...
Monday, December 8, 2014 at 6:00pm
1.The Census Bureau estimates that in 2025, 20 of 50 states will have a Spanish-speaking majority. What percent of the states will have a Spanish-speaking majority? A. 20% B. 30% C. 40%*** D. 50% 2. What percent of 25 is 10? A. 10=p*25;40% B. 10=p*25;250% C. 25=p*10;40% D. 25=...
Monday, December 8, 2014 at 5:47pm
1.Liam wants to buy a bicycle that costs $290.00. His parents say Liam must raise 40% of the money himself. How much money must Liam raise? A. $112.00 B. $40.00 C. $116.00*** D. $87.00 2.Solve the proportion using cross products 29 miles/58 hours=10 miles/ h hours A. 10 B. 20...
Monday, December 8, 2014 at 5:31pm
1.Write the fraction 8/9 as a percent. Round to the nearest hundereth of a percent where necessary. A. 88.89%*** B. 1.13% C. 44.44% D. 66.67% 2.Write the decimal 0.237 as a percent. A. 0.237% B. 2.37% C. 23.7%*** D. 237% 3.Jerry sold 7/20 of the total number of tickets that ...
Monday, December 8, 2014 at 5:17pm
A punch recipe says to mix 4 cups of pineapple juice, 8 cups of orange juice, and 12 cups seltzer in order to make 18 servings of punch. How many cups of each ingredient do you need to make 108 cups of punch? ----- cups of pineapple juice ----- cups orange juice - ----- cups ...
Monday, December 8, 2014 at 4:49pm
Evaluate 2/(1+J4)^2 I got as far as: (1+j4)^2=(1+j4)(1+j4)=1+j4+j4+j4^2=1+J24 OR (1+j4)^2 (/2) =(0.25+j)(0.25+j)=0.0625+j+j+j^2 =0.0625+j+j-0.0625=J^2 I think it can be take further. but im not sure i'm right.
Monday, December 8, 2014 at 1:38pm
A, B, C and D each had some money. D doubled the amounts with the others. C then doubled the amounts with others. B then doubled the amounts with the others. A then doubled the amounts with the others. At this stage, each of them has $80. Find the initial amount with C. Help ...
Monday, December 8, 2014 at 1:26pm
How would I simplify this quadratic equation: y=-15/20.25(x^2+3x+2.25)+0 This is my work already done the original equation I was given but I need help simplifying the equation I have found.
Monday, December 8, 2014 at 12:20pm
A facility has a curent salary budget of $750,000 with a planned salary increase for the next year of 3.5%. Inflation will impact the expense budget by 5%. WHAT WILL BE THE SALARY BUDGET FOR NEXT YEAR?
Monday, December 8, 2014 at 12:12pm
A fair 6 sided dice is marked with the numbers 1, 2, 3, 4,5, and 6. The dice is rolled three times and the results are added. How many different sums are possible?
Monday, December 8, 2014 at 11:38am
What is the approximate cost of florring for a 40ft by 40ft meeting room if half of the room will be carpet at $25 per square yard and other half will be VCT at $2.50 per square foot?
Monday, December 8, 2014 at 11:12am
: The Crescent Corporation just paid a dividend of $2 per share and is expected to continue paying the same amount each year for the next 4 years. If you have a required rate of return of 13%, plan to hold the stock for 4 years, and are confident that it will sell for $30 at ...
Monday, December 8, 2014 at 11:03am
Moore Company is about to issue a bond with semiannual coupon payments, a coupon rate of 8%, and par value of $1,000. The yield-to-maturity for this bond is 10%.
Monday, December 8, 2014 at 10:52am
Part B: The Crescent Corporation just paid a dividend of $2 per share and is expected to continue paying the same amount each year for the next 4 years. If you have a required rate of return of 13%, plan to hold the stock for 4 years, and are confident that it will sell for $...
Monday, December 8, 2014 at 10:49am
The Crescent Corporation just paid a dividend of $2 per share and is expected to continue paying the same amount each year for the next 4 years. If you have a required rate of return of 13%, plan to hold the stock for 4 years, and are confident that it will sell for $30 at the...
Monday, December 8, 2014 at 10:47am
John and Smith went to a stationery shop. John bought 6 pens, 4 pencils and 3 erasers. Smith bought 3 pens, 8 pencils and 6 erasers and spent 20% more than John. What percentage money did John spend on pens? How can I form an equation and solve?
Monday, December 8, 2014 at 6:34am
The sum of two numbers is 4 and the reciprocal of one exceeds the reciprocal of other by twice the product of their reciprocals. What is the product of the reciprocals of two numbers? Please help me solving.
Monday, December 8, 2014 at 2:41am
Please help me set up these problems. 1.) Find an equivalent equation in rectangular coordinates. r(1 - 2 cos θ) = 1 2.) Find a rectangular equation for the plane curve defined by the parametric equations. x = sec t, y = tan 3.) A projectile is fired with an initial ...
Monday, December 8, 2014 at 1:01am
1.) Find all solutions of the equation. Leave answers in trigonometric form. x^2 + 1 - sqrt3i = 0 2.) Give the rectangular coordinates for the point. (9, 2pi/3) 3.) The rectangular coordinates of a point are given. Express the point in polar coordinates with r L 0 and 0° K...
Monday, December 8, 2014 at 12:21am
Francis is baking cookies. The recipe for chocolate chip cookies calls for 2 2/3 cups of flour, the recipe for peanut butter coolies calls for 2.75 cups, the recipe for ginger snaps calls for 5/2 cups. If francis wants to use as little flour as possible, which cookie whould he...
Monday, December 8, 2014 at 12:03am
An animal shelter has 24 large cages and 42 small cages that need to be cleaned. The director of the shelter wants to divide the work so that each person cleans the same number of large cages and the same number of small cages. What is the largest number of people he can use ...
Monday, December 8, 2014 at 12:00am
1.) Write the complex number in trigonometric form r(cos theta + i sin theta) with theta in the interval [0°, 360°). 9 sqrt 3 + 9i 2.) Find the product. Write the product in rectangular form, using exact values. [4 cis 30°] [5 cis 120°] 3.) [4(cos 135° + i ...
Sunday, December 7, 2014 at 11:23pm
The Empire Carpet Company orders merchandise for $14,486, including $475 in shipping charges, from Mohawk Carpet Mills on May 4. Carpets valued at $1,453 will be returned because they are damaged. The terms of sale are 2/10, n/30 ROG. The shipment arrives on May 26, and Empire...
Sunday, December 7, 2014 at 10:50pm
Compute Mary's estimated tax payment for the first quarter. She is self-employed and she expects to earn $61,440 this year. Her estimated income tax rate is 22%. For self-employed persons, social security tax is 12.4% of wages up to $106,800, and Medicare tax is 2.9% of ...
Sunday, December 7, 2014 at 10:47pm
An object is dropped from a balloon from a height of 500m. (a) How long does it take to reach the ground? (b) If the object has an initial velocity of 12m/s, how long does it take to reach the ground? How far will it fall in 5 secnds?
Sunday, December 7, 2014 at 10:23pm
The sum of the squares of three consecutive whole numbers is 77. Form a quadratic equation and hence solve it to determine the numbers. (Hint: let the three consecutive numbers be x, x+1 and x+2)
Sunday, December 7, 2014 at 10:03pm
A ladder 10 ft long leans against a wall. The bottom of the ladder is 6 ft from the wall. How much would the lower end of the ladder have to be pulled away so that the top end would be pulled down by 3 ft?
Sunday, December 7, 2014 at 10:00pm
Two trains are on the same track a distance 100 km apart heading towards one another, each at a speed of 50 km/h. A fly starting out at the front of one train, flies towards the other at a speed of 75 km/h. Upon reaching the other train, the fly turns around and continues ...
Sunday, December 7, 2014 at 9:00pm
For a savings account paying 2.4% in which interest is compounded MONTHLY. FIND THE Time needed to double the initial investment of 10000 dollars. The answer is 28.9 years but WHY
Sunday, December 7, 2014 at 8:54pm
The radioactive isotope sodium-24 is used as a tracer to measure the rate of flow in an artery or vein. The half life of sodium-24 is 14.9 hours.Suppose that a hospital buys a sample of sodium-24 a. how much of the sample will remain AFTER 48 Hours? b. How long will it be ...
Sunday, December 7, 2014 at 8:10pm
math 211(linear algebra)
uppose that the sequence x0, x1, x2... is defined by x0 = 4, x1 = 2, and xk+2 = 4xk+1+5xk for k≥0. Find a general formula for xk. Be sure to include parentheses where necessary, e.g. to distinguish 1/(2k) from 1/2k. .
Sunday, December 7, 2014 at 6:55pm
A bottle rocket travels along a parabolic path and reaches a maximum height of 21 feet after traveling a horizontal distance of 7 feet. A) Write a quadratic function of the form y=a(x-h)^2 +k that models the bottle rocket's path, assuming it leaves the ground at the point...
Sunday, December 7, 2014 at 4:16pm