| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.17 |
| Score | 0% | 63% |
4! = ?
4 x 3 x 2 x 1 |
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4 x 3 |
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5 x 4 x 3 x 2 x 1 |
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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.
The total water usage for a city is 30,000 gallons each day. Of that total, 34% 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?
| 2,200 | |
| 1,700 | |
| 7,500 | |
| 4,800 |
50% of the water consumption is industrial use and 34% is personal use so (50% - 34%) = 16% more water is used for industrial purposes. 30,000 gallons are consumed daily so industry consumes \( \frac{16}{100} \) x 30,000 gallons = 4,800 gallons.
What is \( \frac{3}{8} \) - \( \frac{2}{10} \)?
| 2 \( \frac{2}{11} \) | |
| \(\frac{7}{40}\) | |
| 2 \( \frac{2}{5} \) | |
| 1 \( \frac{6}{15} \) |
To subtract 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 10 are [10, 20, 30, 40, 50, 60, 70, 80, 90]. The first few multiples they share are [40, 80] making 40 the smallest multiple 8 and 10 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{3 x 5}{8 x 5} \) - \( \frac{2 x 4}{10 x 4} \)
\( \frac{15}{40} \) - \( \frac{8}{40} \)
Now, because the fractions share a common denominator, you can subtract them:
\( \frac{15 - 8}{40} \) = \( \frac{7}{40} \) = \(\frac{7}{40}\)
A tiger in a zoo has consumed 70 pounds of food in 7 days. If the tiger continues to eat at the same rate, in how many more days will its total food consumtion be 140 pounds?
| 7 | |
| 10 | |
| 8 | |
| 3 |
If the tiger has consumed 70 pounds of food in 7 days that's \( \frac{70}{7} \) = 10 pounds of food per day. The tiger needs to consume 140 - 70 = 70 more pounds of food to reach 140 pounds total. At 10 pounds of food per day that's \( \frac{70}{10} \) = 7 more days.
\({b + c \over a} = {b \over a} + {c \over a}\) defines which of the following?
distributive property for multiplication |
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commutative property for multiplication |
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distributive property for division |
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commutative property for division |
The distributive property for division helps in solving expressions like \({b + c \over a}\). It specifies that the result of dividing a fraction with multiple terms in the numerator and one term in the denominator can be obtained by dividing each term individually and then totaling the results: \({b + c \over a} = {b \over a} + {c \over a}\). For example, \({a^3 + 6a^2 \over a^2} = {a^3 \over a^2} + {6a^2 \over a^2} = a + 6\).