| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.58 |
| Score | 0% | 72% |
What is 3a2 + 9a2?
| 6a-2 | |
| -6a2 | |
| -6a-2 | |
| 12a2 |
To add or subtract terms with exponents, both the base and the exponent must be the same. In this case they are so add the coefficients and retain the base and exponent:
3a2 + 9a2
(3 + 9)a2
12a2
If a car travels 135 miles in 3 hours, what is the average speed?
| 45 mph | |
| 40 mph | |
| 25 mph | |
| 20 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 \( \frac{3}{7} \) x \( \frac{4}{9} \)?
| \(\frac{4}{21}\) | |
| \(\frac{1}{20}\) | |
| 1\(\frac{1}{3}\) | |
| \(\frac{4}{81}\) |
To multiply fractions, multiply the numerators together and then multiply the denominators together:
\( \frac{3}{7} \) x \( \frac{4}{9} \) = \( \frac{3 x 4}{7 x 9} \) = \( \frac{12}{63} \) = \(\frac{4}{21}\)
What is the greatest common factor of 16 and 28?
| 4 | |
| 5 | |
| 14 | |
| 9 |
The factors of 16 are [1, 2, 4, 8, 16] and the factors of 28 are [1, 2, 4, 7, 14, 28]. They share 3 factors [1, 2, 4] making 4 the greatest factor 16 and 28 have in common.
A menswear store is having a sale: "Buy one shirt at full price and get another shirt for 35% off." If Charlie buys two shirts, each with a regular price of $39, how much will he pay for both shirts?
| $64.35 | |
| $13.65 | |
| $25.35 | |
| $48.75 |
By buying two shirts, Charlie will save $39 x \( \frac{35}{100} \) = \( \frac{$39 x 35}{100} \) = \( \frac{$1365}{100} \) = $13.65 on the second shirt.
So, his total cost will be
$39.00 + ($39.00 - $13.65)
$39.00 + $25.35
$64.35