| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.49 |
| Score | 0% | 70% |
If \( \left|c + 2\right| \) + 2 = -1, which of these is a possible value for c?
| 17 | |
| 1 | |
| -9 | |
| 11 |
First, solve for \( \left|c + 2\right| \):
\( \left|c + 2\right| \) + 2 = -1
\( \left|c + 2\right| \) = -1 - 2
\( \left|c + 2\right| \) = -3
The value inside the absolute value brackets can be either positive or negative so (c + 2) must equal - 3 or --3 for \( \left|c + 2\right| \) to equal -3:
| c + 2 = -3 c = -3 - 2 c = -5 | c + 2 = 3 c = 3 - 2 c = 1 |
So, c = 1 or c = -5.
If a car travels 300 miles in 4 hours, what is the average speed?
| 55 mph | |
| 65 mph | |
| 60 mph | |
| 75 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 \( \frac{1}{8} \) x \( \frac{2}{8} \)?
| \(\frac{1}{4}\) | |
| \(\frac{1}{32}\) | |
| \(\frac{1}{27}\) | |
| \(\frac{1}{14}\) |
To multiply fractions, multiply the numerators together and then multiply the denominators together:
\( \frac{1}{8} \) x \( \frac{2}{8} \) = \( \frac{1 x 2}{8 x 8} \) = \( \frac{2}{64} \) = \(\frac{1}{32}\)
If \(\left|a\right| = 7\), which of the following best describes a?
none of these is correct |
|
a = 7 or a = -7 |
|
a = 7 |
|
a = -7 |
The absolute value is the positive magnitude of a particular number or variable and is indicated by two vertical lines: \(\left|-5\right| = 5\). In the case of a variable absolute value (\(\left|a\right| = 5\)) the value of a can be either positive or negative (a = -5 or a = 5).
Which of the following is not a prime number?
5 |
|
7 |
|
2 |
|
9 |
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.