| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.27 |
| Score | 0% | 65% |
A machine in a factory has an error rate of 4 parts per 100. The machine normally runs 24 hours a day and produces 8 parts per hour. Yesterday the machine was shut down for 4 hours for maintenance.
How many error-free parts did the machine produce yesterday?
| 149.4 | |
| 141.1 | |
| 132.3 | |
| 153.6 |
The hourly error rate for this machine is the error rate in parts per 100 multiplied by the number of parts produced per hour:
\( \frac{4}{100} \) x 8 = \( \frac{4 \times 8}{100} \) = \( \frac{32}{100} \) = 0.32 errors per hour
So, in an average hour, the machine will produce 8 - 0.32 = 7.68 error free parts.
The machine ran for 24 - 4 = 20 hours yesterday so you would expect that 20 x 7.68 = 153.6 error free parts were produced yesterday.
This property states taht the order of addition or multiplication does not mater. For example, 2 + 5 and 5 + 2 are equivalent.
associative |
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commutative |
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PEDMAS |
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distributive |
The commutative property states that, when adding or multiplying numbers, the order in which they're added or multiplied does not matter. For example, 3 + 4 and 4 + 3 give the same result, as do 3 x 4 and 4 x 3.
A bread recipe calls for 1\(\frac{7}{8}\) cups of flour. If you only have 1\(\frac{3}{4}\) cups, how much more flour is needed?
| 1\(\frac{3}{8}\) cups | |
| 2\(\frac{3}{8}\) cups | |
| \(\frac{1}{8}\) cups | |
| \(\frac{1}{4}\) cups |
The amount of flour you need is (1\(\frac{7}{8}\) - 1\(\frac{3}{4}\)) cups. Rewrite the quantities so they share a common denominator and subtract:
(\( \frac{15}{8} \) - \( \frac{14}{8} \)) cups
\( \frac{1}{8} \) cups
\(\frac{1}{8}\) cups
How many 8-passenger vans will it take to drive all 99 members of the football team to an away game?
| 3 vans | |
| 2 vans | |
| 13 vans | |
| 12 vans |
Calculate the number of vans needed by dividing the number of people that need transported by the capacity of one van:
vans = \( \frac{99}{8} \) = 12\(\frac{3}{8}\)
So, it will take 12 full vans and one partially full van to transport the entire team making a total of 13 vans.
Alex loaned Bob $300 at an annual interest rate of 1%. If no payments are made, what is the interest owed on this loan at the end of the first year?
| $42 | |
| $3 | |
| $56 | |
| $5 |
The yearly interest charged on this loan is the annual interest rate multiplied by the amount borrowed:
interest = annual interest rate x loan amount
i = (\( \frac{6}{100} \)) x $300
i = 0.01 x $300
i = $3