| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.18 |
| Score | 0% | 64% |
What is \( 7 \)\( \sqrt{32} \) - \( 5 \)\( \sqrt{2} \)
| 35\( \sqrt{16} \) | |
| 23\( \sqrt{2} \) | |
| 2\( \sqrt{-12} \) | |
| 2\( \sqrt{64} \) |
To subtract these radicals together their radicands must be the same:
7\( \sqrt{32} \) - 5\( \sqrt{2} \)
7\( \sqrt{16 \times 2} \) - 5\( \sqrt{2} \)
7\( \sqrt{4^2 \times 2} \) - 5\( \sqrt{2} \)
(7)(4)\( \sqrt{2} \) - 5\( \sqrt{2} \)
28\( \sqrt{2} \) - 5\( \sqrt{2} \)
Now that the radicands are identical, you can subtract them:
28\( \sqrt{2} \) - 5\( \sqrt{2} \)Which of the following is a mixed number?
\({a \over 5} \) |
|
\(1 {2 \over 5} \) |
|
\({7 \over 5} \) |
|
\({5 \over 7} \) |
A rational number (or fraction) is represented as a ratio between two integers, a and b, and has the form \({a \over b}\) where a is the numerator and b is the denominator. An improper fraction (\({5 \over 3} \)) has a numerator with a greater absolute value than the denominator and can be converted into a mixed number (\(1 {2 \over 3} \)) which has a whole number part and a fractional part.
If all of a roofing company's 8 workers are required to staff 2 roofing crews, how many workers need to be added during the busy season in order to send 5 complete crews out on jobs?
| 12 | |
| 10 | |
| 9 | |
| 16 |
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 8 workers at the company now and that's enough to staff 2 crews so there are \( \frac{8}{2} \) = 4 workers on a crew. 5 crews are needed for the busy season which, at 4 workers per crew, means that the roofing company will need 5 x 4 = 20 total workers to staff the crews during the busy season. The company already employs 8 workers so they need to add 20 - 8 = 12 new staff for the busy season.
What is \( \sqrt{\frac{49}{36}} \)?
| 1\(\frac{3}{5}\) | |
| 1\(\frac{1}{6}\) | |
| 2 | |
| \(\frac{5}{7}\) |
To take the square root of a fraction, break the fraction into two separate roots then calculate the square root of the numerator and denominator separately:
\( \sqrt{\frac{49}{36}} \)
\( \frac{\sqrt{49}}{\sqrt{36}} \)
\( \frac{\sqrt{7^2}}{\sqrt{6^2}} \)
\( \frac{7}{6} \)
1\(\frac{1}{6}\)
What is \( \frac{3}{9} \) ÷ \( \frac{2}{8} \)?
| \(\frac{4}{63}\) | |
| \(\frac{1}{45}\) | |
| 12 | |
| 1\(\frac{1}{3}\) |
To divide fractions, invert the second fraction and then multiply:
\( \frac{3}{9} \) ÷ \( \frac{2}{8} \) = \( \frac{3}{9} \) x \( \frac{8}{2} \)
To multiply fractions, multiply the numerators together and then multiply the denominators together:
\( \frac{3}{9} \) x \( \frac{8}{2} \) = \( \frac{3 x 8}{9 x 2} \) = \( \frac{24}{18} \) = 1\(\frac{1}{3}\)