| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.28 |
| Score | 0% | 66% |
A factor is a positive __________ that divides evenly into a given number.
integer |
|
mixed number |
|
fraction |
|
improper fraction |
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.
What is the greatest common factor of 68 and 32?
| 4 | |
| 18 | |
| 19 | |
| 3 |
The factors of 68 are [1, 2, 4, 17, 34, 68] and the factors of 32 are [1, 2, 4, 8, 16, 32]. They share 3 factors [1, 2, 4] making 4 the greatest factor 68 and 32 have in common.
If there were a total of 350 raffle tickets sold and you bought 7 tickets, what's the probability that you'll win the raffle?
| 11% | |
| 16% | |
| 2% | |
| 14% |
You have 7 out of the total of 350 raffle tickets sold so you have a (\( \frac{7}{350} \)) x 100 = \( \frac{7 \times 100}{350} \) = \( \frac{700}{350} \) = 2% chance to win the raffle.
This property states taht the order of addition or multiplication does not mater. For example, 2 + 5 and 5 + 2 are equivalent.
commutative |
|
PEDMAS |
|
associative |
|
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 machine in a factory has an error rate of 5 parts per 100. The machine normally runs 24 hours a day and produces 8 parts per hour. Yesterday the machine was shut down for 3 hours for maintenance.
How many error-free parts did the machine produce yesterday?
| 159.6 | |
| 159 | |
| 99.8 | |
| 142.9 |
The hourly error rate for this machine is the error rate in parts per 100 multiplied by the number of parts produced per hour:
\( \frac{5}{100} \) x 8 = \( \frac{5 \times 8}{100} \) = \( \frac{40}{100} \) = 0.4 errors per hour
So, in an average hour, the machine will produce 8 - 0.4 = 7.6 error free parts.
The machine ran for 24 - 3 = 21 hours yesterday so you would expect that 21 x 7.6 = 159.6 error free parts were produced yesterday.