| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.69 |
| Score | 0% | 54% |
Which of the following statements about exponents is false?
b0 = 1 |
|
b1 = b |
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all of these are false |
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b1 = 1 |
A number with an exponent (be) consists of a base (b) raised to a power (e). The exponent indicates the number of times that the base is multiplied by itself. A base with an exponent of 1 equals the base (b1 = b) and a base with an exponent of 0 equals 1 ( (b0 = 1).
What is \( \frac{8}{4} \) + \( \frac{6}{8} \)?
| 1 \( \frac{4}{8} \) | |
| 2 \( \frac{1}{8} \) | |
| 2\(\frac{3}{4}\) | |
| 1 \( \frac{9}{8} \) |
To add these fractions, first find the lowest common multiple of their denominators. The first few multiples of 4 are [4, 8, 12, 16, 20, 24, 28, 32, 36, 40] and the first few multiples of 8 are [8, 16, 24, 32, 40, 48, 56, 64, 72, 80]. The first few multiples they share are [8, 16, 24, 32, 40] making 8 the smallest multiple 4 and 8 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{8 x 2}{4 x 2} \) + \( \frac{6 x 1}{8 x 1} \)
\( \frac{16}{8} \) + \( \frac{6}{8} \)
Now, because the fractions share a common denominator, you can add them:
\( \frac{16 + 6}{8} \) = \( \frac{22}{8} \) = 2\(\frac{3}{4}\)
A sports card collection contains football, baseball, and basketball cards. If the ratio of football to baseball cards is 3 to 2 and the ratio of baseball to basketball cards is 3 to 1, what is the ratio of football to basketball cards?
| 7:1 | |
| 7:6 | |
| 3:8 | |
| 9:2 |
The ratio of football cards to baseball cards is 3:2 and the ratio of baseball cards to basketball cards is 3:1. 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 9:6 and the ratio of baseball cards to basketball cards as 6:2. So, the ratio of football cards to basketball cards is football:baseball, baseball:basketball or 9:6, 6:2 which reduces to 9:2.
| 1 | |
| 1.5 | |
| 5.4 | |
| 1.8 |
1
The total water usage for a city is 30,000 gallons each day. Of that total, 22% is for personal use and 50% is for industrial use. How many more gallons of water each day is consumed for industrial use over personal use?
| 5,200 | |
| 8,400 | |
| 5,800 | |
| 1,250 |
50% of the water consumption is industrial use and 22% is personal use so (50% - 22%) = 28% more water is used for industrial purposes. 30,000 gallons are consumed daily so industry consumes \( \frac{28}{100} \) x 30,000 gallons = 8,400 gallons.