| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.74 |
| Score | 0% | 55% |
Cooks are needed to prepare for a large party. Each cook can bake either 3 large cakes or 17 small cakes per hour. The kitchen is available for 3 hours and 32 large cakes and 150 small cakes need to be baked.
How many cooks are required to bake the required number of cakes during the time the kitchen is available?
| 11 | |
| 15 | |
| 7 | |
| 5 |
If a single cook can bake 3 large cakes per hour and the kitchen is available for 3 hours, a single cook can bake 3 x 3 = 9 large cakes during that time. 32 large cakes are needed for the party so \( \frac{32}{9} \) = 3\(\frac{5}{9}\) cooks are needed to bake the required number of large cakes.
If a single cook can bake 17 small cakes per hour and the kitchen is available for 3 hours, a single cook can bake 17 x 3 = 51 small cakes during that time. 150 small cakes are needed for the party so \( \frac{150}{51} \) = 2\(\frac{16}{17}\) cooks are needed to bake the required number of small cakes.
Because you can't employ a fractional cook, round the number of cooks needed for each type of cake up to the next whole number resulting in 4 + 3 = 7 cooks.
What is \( 6 \)\( \sqrt{27} \) - \( 2 \)\( \sqrt{3} \)
| 16\( \sqrt{3} \) | |
| 12\( \sqrt{3} \) | |
| 12\( \sqrt{27} \) | |
| 12\( \sqrt{9} \) |
To subtract these radicals together their radicands must be the same:
6\( \sqrt{27} \) - 2\( \sqrt{3} \)
6\( \sqrt{9 \times 3} \) - 2\( \sqrt{3} \)
6\( \sqrt{3^2 \times 3} \) - 2\( \sqrt{3} \)
(6)(3)\( \sqrt{3} \) - 2\( \sqrt{3} \)
18\( \sqrt{3} \) - 2\( \sqrt{3} \)
Now that the radicands are identical, you can subtract them:
18\( \sqrt{3} \) - 2\( \sqrt{3} \)What is 6\( \sqrt{2} \) x 7\( \sqrt{8} \)?
| 42\( \sqrt{8} \) | |
| 42\( \sqrt{10} \) | |
| 168 | |
| 13\( \sqrt{8} \) |
To multiply terms with radicals, multiply the coefficients and radicands separately:
6\( \sqrt{2} \) x 7\( \sqrt{8} \)
(6 x 7)\( \sqrt{2 \times 8} \)
42\( \sqrt{16} \)
Now we need to simplify the radical:
42\( \sqrt{16} \)
42\( \sqrt{4^2} \)
(42)(4)
168
What is \( \frac{3}{7} \) ÷ \( \frac{1}{8} \)?
| 3\(\frac{3}{7}\) | |
| \(\frac{1}{4}\) | |
| \(\frac{3}{32}\) | |
| \(\frac{1}{6}\) |
To divide fractions, invert the second fraction and then multiply:
\( \frac{3}{7} \) ÷ \( \frac{1}{8} \) = \( \frac{3}{7} \) x \( \frac{8}{1} \)
To multiply fractions, multiply the numerators together and then multiply the denominators together:
\( \frac{3}{7} \) x \( \frac{8}{1} \) = \( \frac{3 x 8}{7 x 1} \) = \( \frac{24}{7} \) = 3\(\frac{3}{7}\)
How many hours does it take a car to travel 210 miles at an average speed of 30 miles per hour?
| 7 hours | |
| 3 hours | |
| 6 hours | |
| 1 hour |
Average speed in miles per hour is the number of miles traveled divided by the number of hours:
speed = \( \frac{\text{distance}}{\text{time}} \)Solving for time:
time = \( \frac{\text{distance}}{\text{speed}} \)
time = \( \frac{210mi}{30mph} \)
7 hours