| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.02 |
| Score | 0% | 60% |
If \(\left|a\right| = 7\), which of the following best describes a?
a = 7 |
|
none of these is correct |
|
a = 7 or 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).
If there were a total of 400 raffle tickets sold and you bought 12 tickets, what's the probability that you'll win the raffle?
| 9% | |
| 3% | |
| 11% | |
| 10% |
You have 12 out of the total of 400 raffle tickets sold so you have a (\( \frac{12}{400} \)) x 100 = \( \frac{12 \times 100}{400} \) = \( \frac{1200}{400} \) = 3% chance to win the raffle.
If \( \left|b - 1\right| \) - 2 = 5, which of these is a possible value for b?
| 3 | |
| -11 | |
| -6 | |
| -5 |
First, solve for \( \left|b - 1\right| \):
\( \left|b - 1\right| \) - 2 = 5
\( \left|b - 1\right| \) = 5 + 2
\( \left|b - 1\right| \) = 7
The value inside the absolute value brackets can be either positive or negative so (b - 1) must equal + 7 or -7 for \( \left|b - 1\right| \) to equal 7:
| b - 1 = 7 b = 7 + 1 b = 8 | b - 1 = -7 b = -7 + 1 b = -6 |
So, b = -6 or b = 8.
Diane scored 77% on her final exam. If each question was worth 4 points and there were 120 possible points on the exam, how many questions did Diane answer correctly?
| 13 | |
| 9 | |
| 23 | |
| 26 |
Diane scored 77% on the test meaning she earned 77% of the possible points on the test. There were 120 possible points on the test so she earned 120 x 0.77 = 92 points. Each question is worth 4 points so she got \( \frac{92}{4} \) = 23 questions right.
If all of a roofing company's 4 workers are required to staff 2 roofing crews, how many workers need to be added during the busy season in order to send 4 complete crews out on jobs?
| 15 | |
| 2 | |
| 4 | |
| 14 |
In order to find how many additional workers are needed to staff the extra crews you first need to calculate how many workers are on a crew. There are 4 workers at the company now and that's enough to staff 2 crews so there are \( \frac{4}{2} \) = 2 workers on a crew. 4 crews are needed for the busy season which, at 2 workers per crew, means that the roofing company will need 4 x 2 = 8 total workers to staff the crews during the busy season. The company already employs 4 workers so they need to add 8 - 4 = 4 new staff for the busy season.