| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.42 |
| Score | 0% | 68% |
The total water usage for a city is 15,000 gallons each day. Of that total, 21% is for personal use and 43% is for industrial use. How many more gallons of water each day is consumed for industrial use over personal use?
| 13,950 | |
| 3,300 | |
| 5,500 | |
| 1,000 |
43% of the water consumption is industrial use and 21% is personal use so (43% - 21%) = 22% more water is used for industrial purposes. 15,000 gallons are consumed daily so industry consumes \( \frac{22}{100} \) x 15,000 gallons = 3,300 gallons.
What is -6b4 - 5b4?
| -11b4 | |
| 11b4 | |
| -11b-4 | |
| -b16 |
To add or subtract terms with exponents, both the base and the exponent must be the same. In this case they are so subtract the coefficients and retain the base and exponent:
-6b4 - 5b4
(-6 - 5)b4
-11b4
4! = ?
4 x 3 x 2 x 1 |
|
4 x 3 |
|
5 x 4 x 3 x 2 x 1 |
|
3 x 2 x 1 |
A factorial has the form n! and is the product of the integer (n) and all the positive integers below it. For example, 5! = 5 x 4 x 3 x 2 x 1 = 120.
What is \( \frac{3}{8} \) x \( \frac{2}{6} \)?
| \(\frac{1}{8}\) | |
| \(\frac{3}{35}\) | |
| \(\frac{1}{9}\) | |
| \(\frac{1}{12}\) |
To multiply fractions, multiply the numerators together and then multiply the denominators together:
\( \frac{3}{8} \) x \( \frac{2}{6} \) = \( \frac{3 x 2}{8 x 6} \) = \( \frac{6}{48} \) = \(\frac{1}{8}\)
A sports card collection contains football, baseball, and basketball cards. If the ratio of football to baseball cards is 9 to 2 and the ratio of baseball to basketball cards is 9 to 1, what is the ratio of football to basketball cards?
| 7:8 | |
| 81:2 | |
| 5:4 | |
| 7:6 |
The ratio of football cards to baseball cards is 9:2 and the ratio of baseball cards to basketball cards is 9:1. To solve this problem, we need the baseball card side of each ratio to be equal so we need to rewrite the ratios in terms of a common number of baseball cards. (Think of this like finding the common denominator when adding fractions.) The ratio of football to baseball cards can also be written as 81:18 and the ratio of baseball cards to basketball cards as 18:2. So, the ratio of football cards to basketball cards is football:baseball, baseball:basketball or 81:18, 18:2 which reduces to 81:2.