| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.46 |
| Score | 0% | 69% |
Which of the following is a mixed number?
\({5 \over 7} \) |
|
\({7 \over 5} \) |
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\(1 {2 \over 5} \) |
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\({a \over 5} \) |
A rational number (or fraction) is represented as a ratio between two integers, a and b, and has the form \({a \over b}\) where a is the numerator and b is the denominator. An improper fraction (\({5 \over 3} \)) has a numerator with a greater absolute value than the denominator and can be converted into a mixed number (\(1 {2 \over 3} \)) which has a whole number part and a fractional part.
A machine in a factory has an error rate of 8 parts per 100. The machine normally runs 24 hours a day and produces 10 parts per hour. Yesterday the machine was shut down for 3 hours for maintenance.
How many error-free parts did the machine produce yesterday?
| 115.4 | |
| 96.9 | |
| 193.2 | |
| 177.7 |
The hourly error rate for this machine is the error rate in parts per 100 multiplied by the number of parts produced per hour:
\( \frac{8}{100} \) x 10 = \( \frac{8 \times 10}{100} \) = \( \frac{80}{100} \) = 0.8 errors per hour
So, in an average hour, the machine will produce 10 - 0.8 = 9.2 error free parts.
The machine ran for 24 - 3 = 21 hours yesterday so you would expect that 21 x 9.2 = 193.2 error free parts were produced yesterday.
What is \( \sqrt{\frac{49}{81}} \)?
| \(\frac{7}{9}\) | |
| 2\(\frac{1}{3}\) | |
| 1\(\frac{2}{7}\) | |
| 1\(\frac{2}{3}\) |
To take the square root of a fraction, break the fraction into two separate roots then calculate the square root of the numerator and denominator separately:
\( \sqrt{\frac{49}{81}} \)
\( \frac{\sqrt{49}}{\sqrt{81}} \)
\( \frac{\sqrt{7^2}}{\sqrt{9^2}} \)
\(\frac{7}{9}\)
A bread recipe calls for 2\(\frac{1}{8}\) cups of flour. If you only have \(\frac{1}{8}\) cup, how much more flour is needed?
| 2 cups | |
| 1\(\frac{1}{2}\) cups | |
| \(\frac{1}{2}\) cups | |
| \(\frac{1}{4}\) cups |
The amount of flour you need is (2\(\frac{1}{8}\) - \(\frac{1}{8}\)) cups. Rewrite the quantities so they share a common denominator and subtract:
(\( \frac{17}{8} \) - \( \frac{1}{8} \)) cups
\( \frac{16}{8} \) cups
2 cups
A factor is a positive __________ that divides evenly into a given number.
mixed number |
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improper fraction |
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fraction |
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integer |
A factor is a positive integer that divides evenly into a given number. For example, the factors of 8 are 1, 2, 4, and 8.