| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.97 |
| Score | 0% | 59% |
Which of the following is not a prime number?
9 |
|
2 |
|
5 |
|
7 |
A prime number is an integer greater than 1 that has no factors other than 1 and itself. Examples of prime numbers include 2, 3, 5, 7, and 11.
A machine in a factory has an error rate of 3 parts per 100. The machine normally runs 24 hours a day and produces 9 parts per hour. Yesterday the machine was shut down for 9 hours for maintenance.
How many error-free parts did the machine produce yesterday?
| 106.4 | |
| 129 | |
| 131 | |
| 161.5 |
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 9 = \( \frac{3 \times 9}{100} \) = \( \frac{27}{100} \) = 0.27 errors per hour
So, in an average hour, the machine will produce 9 - 0.27 = 8.73 error free parts.
The machine ran for 24 - 9 = 15 hours yesterday so you would expect that 15 x 8.73 = 131 error free parts were produced yesterday.
Roger loaned Roger $800 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?
| $20 | |
| $39 | |
| $99 | |
| $8 |
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 $800
i = 0.01 x $800
i = $8
If \(\left|a\right| = 7\), which of the following best describes a?
a = 7 or a = -7 |
|
a = -7 |
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none of these is correct |
|
a = 7 |
The absolute value is the positive magnitude of a particular number or variable and is indicated by two vertical lines: \(\left|-5\right| = 5\). In the case of a variable absolute value (\(\left|a\right| = 5\)) the value of a can be either positive or negative (a = -5 or a = 5).
Cooks are needed to prepare for a large party. Each cook can bake either 4 large cakes or 17 small cakes per hour. The kitchen is available for 4 hours and 37 large cakes and 350 small cakes need to be baked.
How many cooks are required to bake the required number of cakes during the time the kitchen is available?
| 5 | |
| 12 | |
| 10 | |
| 9 |
If a single cook can bake 4 large cakes per hour and the kitchen is available for 4 hours, a single cook can bake 4 x 4 = 16 large cakes during that time. 37 large cakes are needed for the party so \( \frac{37}{16} \) = 2\(\frac{5}{16}\) cooks are needed to bake the required number of large cakes.
If a single cook can bake 17 small cakes per hour and the kitchen is available for 4 hours, a single cook can bake 17 x 4 = 68 small cakes during that time. 350 small cakes are needed for the party so \( \frac{350}{68} \) = 5\(\frac{5}{34}\) cooks are needed to bake the required number of small cakes.
Because you can't employ a fractional cook, round the number of cooks needed for each type of cake up to the next whole number resulting in 3 + 6 = 9 cooks.