| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.30 |
| Score | 0% | 66% |
Which of the following is not a prime number?
9 |
|
5 |
|
2 |
|
7 |
A prime number is an integer greater than 1 that has no factors other than 1 and itself. Examples of prime numbers include 2, 3, 5, 7, and 11.
How many hours does it take a car to travel 160 miles at an average speed of 20 miles per hour?
| 8 hours | |
| 4 hours | |
| 9 hours | |
| 6 hours |
Average speed in miles per hour is the number of miles traveled divided by the number of hours:
speed = \( \frac{\text{distance}}{\text{time}} \)Solving for time:
time = \( \frac{\text{distance}}{\text{speed}} \)
time = \( \frac{160mi}{20mph} \)
8 hours
What is \( \frac{7y^8}{3y^4} \)?
| 2\(\frac{1}{3}\)y-4 | |
| \(\frac{3}{7}\)y-4 | |
| 2\(\frac{1}{3}\)y4 | |
| \(\frac{3}{7}\)y4 |
To divide terms with exponents, the base of both exponents must be the same. In this case they are so divide the coefficients and subtract the exponents:
\( \frac{7y^8}{3y^4} \)
\( \frac{7}{3} \) y(8 - 4)
2\(\frac{1}{3}\)y4
If a rectangle is twice as long as it is wide and has a perimeter of 12 meters, what is the area of the rectangle?
| 98 m2 | |
| 8 m2 | |
| 18 m2 | |
| 50 m2 |
The area of a rectangle is width (w) x height (h). In this problem we know that the rectangle is twice as long as it is wide so h = 2w. The perimeter of a rectangle is 2w + 2h and we know that the perimeter of this rectangle is 12 meters so the equation becomes: 2w + 2h = 12.
Putting these two equations together and solving for width (w):
2w + 2h = 12
w + h = \( \frac{12}{2} \)
w + h = 6
w = 6 - h
From the question we know that h = 2w so substituting 2w for h gives us:
w = 6 - 2w
3w = 6
w = \( \frac{6}{3} \)
w = 2
Since h = 2w that makes h = (2 x 2) = 4 and the area = h x w = 2 x 4 = 8 m2
What is the least common multiple of 4 and 12?
| 43 | |
| 33 | |
| 28 | |
| 12 |
The first few multiples of 4 are [4, 8, 12, 16, 20, 24, 28, 32, 36, 40] and the first few multiples of 12 are [12, 24, 36, 48, 60, 72, 84, 96]. The first few multiples they share are [12, 24, 36, 48, 60] making 12 the smallest multiple 4 and 12 have in common.