| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.42 |
| Score | 0% | 68% |
If a car travels 240 miles in 4 hours, what is the average speed?
| 60 mph | |
| 25 mph | |
| 65 mph | |
| 45 mph |
Average speed in miles per hour is the number of miles traveled divided by the number of hours:
speed = \( \frac{\text{distance}}{\text{time}} \)What is the next number in this sequence: 1, 10, 19, 28, 37, __________ ?
| 49 | |
| 51 | |
| 46 | |
| 53 |
The equation for this sequence is:
an = an-1 + 9
where n is the term's order in the sequence, an is the value of the term, and an-1 is the value of the term before an. This makes the next number:
a6 = a5 + 9
a6 = 37 + 9
a6 = 46
A machine in a factory has an error rate of 3 parts per 100. The machine normally runs 24 hours a day and produces 10 parts per hour. Yesterday the machine was shut down for 5 hours for maintenance.
How many error-free parts did the machine produce yesterday?
| 184.3 | |
| 190.1 | |
| 215.6 | |
| 112.8 |
The hourly error rate for this machine is the error rate in parts per 100 multiplied by the number of parts produced per hour:
\( \frac{3}{100} \) x 10 = \( \frac{3 \times 10}{100} \) = \( \frac{30}{100} \) = 0.3 errors per hour
So, in an average hour, the machine will produce 10 - 0.3 = 9.7 error free parts.
The machine ran for 24 - 5 = 19 hours yesterday so you would expect that 19 x 9.7 = 184.3 error free parts were produced yesterday.
Which of these numbers is a factor of 40?
| 28 | |
| 8 | |
| 22 | |
| 33 |
The factors of a number are all positive integers that divide evenly into the number. The factors of 40 are 1, 2, 4, 5, 8, 10, 20, 40.
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?
| 72 m2 | |
| 8 m2 | |
| 32 m2 | |
| 162 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