I got a few questions wrong and i would like some explanations on these question:
2. A pair of pants sells for $6 more than 75% of its price of the pants?
A.$12
B.$18
C.$20
D.$24
E.$36
Choice E is wrong.
4. What is the wall thickness, inches, of a tube with an outer diameter of 0.750 and an inner diameter of 0.625?
A.0.0625
B.0.125
C.0.625
D.0.6875
E.0.750
Choice B is wrong.
14.In the figure below. AC and BD are chords of a circle that intersect at point E (E point is not shown). AD is the diameter of this circle. If the measure of arc AB=40 degrees and <CED=60 degrees, what i the measure of <CAD?
A.60 degrees
B.45 degrees
C.30 degrees
D.40 degrees
E.15 degrees
Choice C is wrong.
24. A gear with 30 teeth revolving at 30 revolutions per minute is meshed with a second gear turning at 250 revolution per minute. How many teeth does this gear have?
A.36
B.25
C.15
D.30
E.24
Choice B is wrong.
#2
A pair of pants sells for $6 more than 75% of its price of the pants?
The question makes no sense.
#4 (A)
0.750 - 0.625 = 0.125
But that is the difference in the diameter. The wall thickness is the difference in radius: half that, or 0.0625
#14 (D)
since AB = 40°, <ADB = 20°
supplementary angle AED = 120°
The remaining angle of triangle AED is 40°
#24 ??
since the speed ratio is 250/30, the tooth ratio is 30/250 * 30 = 3.6
You sure that the speed is not 25.0 rpm? That would make the choice (A).
its 300 revolutions per minutes. I made a mistake
2. A pair of pants sell for $6 more than 75% of its price. What is the price of the pants?
2.
x = .75x + 6
.25x = 6
x = 24
4.
outer radius = .75/2 = .375
inner radius = .625/2 = .3125
so thickness of wall = .375-.3125 = .0625
14. no diagram
24.
Think of the teeth laid out linearly
For the first gear in 1 minute would cover 30x30 or 900 teeth
for the 2nd gear, let the number of teeth be x
then 250x = 900
x = 900/250 = 3.6 ????
mmmhhh? , typo? or flaw in my thinking
in question 24,it is 300 revolution per minute, not 30 revolution per minute.
that would make it 900/300 = 3
a gear with 3 teeth ????
In that case, the speed ratio is 250/300, so the teeth ratio will be 300/250 * 30 = 36
I do not understand number 2. Typo?
4) .75/2 -.625/2 = .0625 (radius not diameter is used)
14) I get 40 (long, will elaborate later)
24) (30/250)(30) = 3.6
2. To solve this question, we need to find the price of the pants. Let's assume the price of the pants is x. According to the information given, the pants sell for $6 more than 75% of their price.
75% of x is 0.75x. Therefore, the price of the pants is 0.75x + $6. We can set up the equation:
0.75x + $6 = x
Subtracting 0.75x from both sides:
$6 = 0.25x
Dividing both sides by 0.25:
x = $24
So, the price of the pants is $24. However, the question is asking for the price difference, which is $6. Therefore, the correct answer is D. $24.
4. To find the wall thickness of the tube, we need to subtract the inner diameter from the outer diameter.
0.750 - 0.625 = 0.125
Therefore, the wall thickness of the tube is 0.125 inches. The correct answer is B. 0.125.
14. In this question, we need to use the properties of angles in a circle.
Since AD is the diameter of the circle, angle ABD and angle ACD are both 90 degrees (as they are inscribed angles that intercept arc AB and arc AC, respectively).
Also, since arc AB measures 40 degrees, arc AC measures 360 - 40 = 320 degrees.
Finally, since angle CED is given to be 60 degrees, angle CAD is half the measure of arc AC, which is 320/2 = 160 degrees.
Therefore, the measure of angle CAD is 160 degrees. The correct answer is not provided in the options, so we cannot determine the correct answer from the given choices.
24. To solve this question, we can use the concept of the gear ratio, which is the ratio of the number of teeth on the two gears.
The gear with 30 teeth is revolving at 30 revolutions per minute, and the second gear is turning at 250 revolutions per minute. The gear ratio is the ratio of their number of revolutions per minute, which is 250/30 = 8.333.
Since the gear ratio is also equal to the ratio of their number of teeth, we can set up the equation:
Number of teeth on the second gear/30 = 8.333
Cross-multiplying:
Number of teeth on the second gear = 8.333 * 30 = 250
Therefore, the second gear has 250 teeth. The correct answer is not provided in the options, so we cannot determine the correct answer from the given choices.