| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.47 |
| Score | 0% | 49% |
What is 2c3 + c3?
| c3 | |
| 3c6 | |
| -c3 | |
| 3c3 |
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:
2c3 + 1c3
(2 + 1)c3
3c3
A circular logo is enlarged to fit the lid of a jar. The new diameter is 45% larger than the original. By what percentage has the area of the logo increased?
| 27\(\frac{1}{2}\)% | |
| 37\(\frac{1}{2}\)% | |
| 22\(\frac{1}{2}\)% | |
| 17\(\frac{1}{2}\)% |
The area of a circle is given by the formula A = πr2 where r is the radius of the circle. The radius of a circle is its diameter divided by two so A = π(\( \frac{d}{2} \))2. If the diameter of the logo increases by 45% the radius (and, consequently, the total area) increases by \( \frac{45\text{%}}{2} \) = 22\(\frac{1}{2}\)%
If the ratio of home fans to visiting fans in a crowd is 3:1 and all 41,000 seats in a stadium are filled, how many home fans are in attendance?
| 31,667 | |
| 30,750 | |
| 30,667 | |
| 36,667 |
A ratio of 3:1 means that there are 3 home fans for every one visiting fan. So, of every 4 fans, 3 are home fans and \( \frac{3}{4} \) of every fan in the stadium is a home fan:
41,000 fans x \( \frac{3}{4} \) = \( \frac{123000}{4} \) = 30,750 fans.
What is 3\( \sqrt{3} \) x 5\( \sqrt{9} \)?
| 8\( \sqrt{9} \) | |
| 45\( \sqrt{3} \) | |
| 15\( \sqrt{3} \) | |
| 8\( \sqrt{27} \) |
To multiply terms with radicals, multiply the coefficients and radicands separately:
3\( \sqrt{3} \) x 5\( \sqrt{9} \)
(3 x 5)\( \sqrt{3 \times 9} \)
15\( \sqrt{27} \)
Now we need to simplify the radical:
15\( \sqrt{27} \)
15\( \sqrt{3 \times 9} \)
15\( \sqrt{3 \times 3^2} \)
(15)(3)\( \sqrt{3} \)
45\( \sqrt{3} \)
Cooks are needed to prepare for a large party. Each cook can bake either 4 large cakes or 20 small cakes per hour. The kitchen is available for 3 hours and 20 large cakes and 250 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?
| 12 | |
| 11 | |
| 14 | |
| 7 |
If a single cook can bake 4 large cakes per hour and the kitchen is available for 3 hours, a single cook can bake 4 x 3 = 12 large cakes during that time. 20 large cakes are needed for the party so \( \frac{20}{12} \) = 1\(\frac{2}{3}\) cooks are needed to bake the required number of large cakes.
If a single cook can bake 20 small cakes per hour and the kitchen is available for 3 hours, a single cook can bake 20 x 3 = 60 small cakes during that time. 250 small cakes are needed for the party so \( \frac{250}{60} \) = 4\(\frac{1}{6}\) 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 2 + 5 = 7 cooks.