| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.74 |
| Score | 0% | 55% |
The __________ is the greatest factor that divides two integers.
greatest common multiple |
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least common multiple |
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absolute value |
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greatest common factor |
The greatest common factor (GCF) is the greatest factor that divides two integers.
What is \( \frac{5}{6} \) - \( \frac{5}{10} \)?
| \( \frac{4}{13} \) | |
| \(\frac{1}{3}\) | |
| 1 \( \frac{8}{11} \) | |
| 2 \( \frac{6}{30} \) |
To subtract these fractions, first find the lowest common multiple of their denominators. The first few multiples of 6 are [6, 12, 18, 24, 30, 36, 42, 48, 54, 60] and the first few multiples of 10 are [10, 20, 30, 40, 50, 60, 70, 80, 90]. The first few multiples they share are [30, 60, 90] making 30 the smallest multiple 6 and 10 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{5 x 5}{6 x 5} \) - \( \frac{5 x 3}{10 x 3} \)
\( \frac{25}{30} \) - \( \frac{15}{30} \)
Now, because the fractions share a common denominator, you can subtract them:
\( \frac{25 - 15}{30} \) = \( \frac{10}{30} \) = \(\frac{1}{3}\)
What is \( 4 \)\( \sqrt{18} \) - \( 5 \)\( \sqrt{2} \)
| 20\( \sqrt{18} \) | |
| -1\( \sqrt{-5} \) | |
| 20\( \sqrt{2} \) | |
| 7\( \sqrt{2} \) |
To subtract these radicals together their radicands must be the same:
4\( \sqrt{18} \) - 5\( \sqrt{2} \)
4\( \sqrt{9 \times 2} \) - 5\( \sqrt{2} \)
4\( \sqrt{3^2 \times 2} \) - 5\( \sqrt{2} \)
(4)(3)\( \sqrt{2} \) - 5\( \sqrt{2} \)
12\( \sqrt{2} \) - 5\( \sqrt{2} \)
Now that the radicands are identical, you can subtract them:
12\( \sqrt{2} \) - 5\( \sqrt{2} \)A tiger in a zoo has consumed 112 pounds of food in 8 days. If the tiger continues to eat at the same rate, in how many more days will its total food consumtion be 154 pounds?
| 1 | |
| 5 | |
| 6 | |
| 3 |
If the tiger has consumed 112 pounds of food in 8 days that's \( \frac{112}{8} \) = 14 pounds of food per day. The tiger needs to consume 154 - 112 = 42 more pounds of food to reach 154 pounds total. At 14 pounds of food per day that's \( \frac{42}{14} \) = 3 more days.
A machine in a factory has an error rate of 3 parts per 100. The machine normally runs 24 hours a day and produces 8 parts per hour. Yesterday the machine was shut down for 8 hours for maintenance.
How many error-free parts did the machine produce yesterday?
| 124.2 | |
| 97.6 | |
| 157.3 | |
| 87.4 |
The hourly error rate for this machine is the error rate in parts per 100 multiplied by the number of parts produced per hour:
\( \frac{3}{100} \) x 8 = \( \frac{3 \times 8}{100} \) = \( \frac{24}{100} \) = 0.24 errors per hour
So, in an average hour, the machine will produce 8 - 0.24 = 7.76 error free parts.
The machine ran for 24 - 8 = 16 hours yesterday so you would expect that 16 x 7.76 = 124.2 error free parts were produced yesterday.