| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.25 |
| Score | 0% | 65% |
If a rectangle is twice as long as it is wide and has a perimeter of 24 meters, what is the area of the rectangle?
| 50 m2 | |
| 128 m2 | |
| 72 m2 | |
| 32 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 24 meters so the equation becomes: 2w + 2h = 24.
Putting these two equations together and solving for width (w):
2w + 2h = 24
w + h = \( \frac{24}{2} \)
w + h = 12
w = 12 - h
From the question we know that h = 2w so substituting 2w for h gives us:
w = 12 - 2w
3w = 12
w = \( \frac{12}{3} \)
w = 4
Since h = 2w that makes h = (2 x 4) = 8 and the area = h x w = 4 x 8 = 32 m2
Find the average of the following numbers: 11, 9, 13, 7.
| 10 | |
| 11 | |
| 9 | |
| 5 |
To find the average of these 4 numbers add them together then divide by 4:
\( \frac{11 + 9 + 13 + 7}{4} \) = \( \frac{40}{4} \) = 10
What is \( \frac{1}{8} \) ÷ \( \frac{4}{7} \)?
| \(\frac{7}{8}\) | |
| \(\frac{7}{32}\) | |
| \(\frac{2}{21}\) | |
| \(\frac{4}{63}\) |
To divide fractions, invert the second fraction and then multiply:
\( \frac{1}{8} \) ÷ \( \frac{4}{7} \) = \( \frac{1}{8} \) x \( \frac{7}{4} \)
To multiply fractions, multiply the numerators together and then multiply the denominators together:
\( \frac{1}{8} \) x \( \frac{7}{4} \) = \( \frac{1 x 7}{8 x 4} \) = \( \frac{7}{32} \) = \(\frac{7}{32}\)
If a mayor is elected with 78% of the votes cast and 83% of a town's 37,000 voters cast a vote, how many votes did the mayor receive?
| 23,647 | |
| 20,576 | |
| 23,033 | |
| 23,954 |
If 83% of the town's 37,000 voters cast ballots the number of votes cast is:
(\( \frac{83}{100} \)) x 37,000 = \( \frac{3,071,000}{100} \) = 30,710
The mayor got 78% of the votes cast which is:
(\( \frac{78}{100} \)) x 30,710 = \( \frac{2,395,380}{100} \) = 23,954 votes.
How many hours does it take a car to travel 140 miles at an average speed of 35 miles per hour?
| 5 hours | |
| 7 hours | |
| 4 hours | |
| 3 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 = \( \frac{140mi}{35mph} \)
4 hours