| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.12 |
| Score | 0% | 62% |
A sports card collection contains football, baseball, and basketball cards. If the ratio of football to baseball cards is 7 to 2 and the ratio of baseball to basketball cards is 7 to 1, what is the ratio of football to basketball cards?
| 49:2 | |
| 1:4 | |
| 5:1 | |
| 1:8 |
The ratio of football cards to baseball cards is 7:2 and the ratio of baseball cards to basketball cards is 7:1. 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 49:14 and the ratio of baseball cards to basketball cards as 14:2. So, the ratio of football cards to basketball cards is football:baseball, baseball:basketball or 49:14, 14:2 which reduces to 49:2.
If \(\left|a\right| = 7\), which of the following best describes a?
a = 7 or a = -7 |
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a = -7 |
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none of these is correct |
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a = 7 |
The absolute value is the positive magnitude of a particular number or variable and is indicated by two vertical lines: \(\left|-5\right| = 5\). In the case of a variable absolute value (\(\left|a\right| = 5\)) the value of a can be either positive or negative (a = -5 or a = 5).
Which of the following is not an integer?
\({1 \over 2}\) |
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-1 |
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1 |
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0 |
An integer is any whole number, including zero. An integer can be either positive or negative. Examples include -77, -1, 0, 55, 119.
How many 2\(\frac{1}{2}\) gallon cans worth of fuel would you need to pour into an empty 15 gallon tank to fill it exactly halfway?
| 8 | |
| 2 | |
| 4 | |
| 3 |
To fill a 15 gallon tank exactly halfway you'll need 7\(\frac{1}{2}\) gallons of fuel. Each fuel can holds 2\(\frac{1}{2}\) gallons so:
cans = \( \frac{7\frac{1}{2} \text{ gallons}}{2\frac{1}{2} \text{ gallons}} \) = 3
What is \( \frac{4}{8} \) + \( \frac{5}{12} \)?
| 1 \( \frac{9}{16} \) | |
| \(\frac{11}{12}\) | |
| 1 \( \frac{7}{13} \) | |
| \( \frac{1}{24} \) |
To add these fractions, first find the lowest common multiple of their denominators. The first few multiples of 8 are [8, 16, 24, 32, 40, 48, 56, 64, 72, 80] and the first few multiples of 12 are [12, 24, 36, 48, 60, 72, 84, 96]. The first few multiples they share are [24, 48, 72, 96] making 24 the smallest multiple 8 and 12 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{4 x 3}{8 x 3} \) + \( \frac{5 x 2}{12 x 2} \)
\( \frac{12}{24} \) + \( \frac{10}{24} \)
Now, because the fractions share a common denominator, you can add them:
\( \frac{12 + 10}{24} \) = \( \frac{22}{24} \) = \(\frac{11}{12}\)