| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.67 |
| Score | 0% | 53% |
If \(\left|a\right| = 7\), which of the following best describes a?
none of these is correct |
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a = -7 |
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a = 7 or a = -7 |
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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).
Which of the following statements about exponents is false?
b0 = 1 |
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all of these are false |
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b1 = b |
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b1 = 1 |
A number with an exponent (be) consists of a base (b) raised to a power (e). The exponent indicates the number of times that the base is multiplied by itself. A base with an exponent of 1 equals the base (b1 = b) and a base with an exponent of 0 equals 1 ( (b0 = 1).
Cooks are needed to prepare for a large party. Each cook can bake either 5 large cakes or 10 small cakes per hour. The kitchen is available for 3 hours and 25 large cakes and 310 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?
| 7 | |
| 11 | |
| 8 | |
| 13 |
If a single cook can bake 5 large cakes per hour and the kitchen is available for 3 hours, a single cook can bake 5 x 3 = 15 large cakes during that time. 25 large cakes are needed for the party so \( \frac{25}{15} \) = 1\(\frac{2}{3}\) cooks are needed to bake the required number of large cakes.
If a single cook can bake 10 small cakes per hour and the kitchen is available for 3 hours, a single cook can bake 10 x 3 = 30 small cakes during that time. 310 small cakes are needed for the party so \( \frac{310}{30} \) = 10\(\frac{1}{3}\) 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 2 + 11 = 13 cooks.
What is 6\( \sqrt{4} \) x 6\( \sqrt{9} \)?
| 12\( \sqrt{4} \) | |
| 36\( \sqrt{13} \) | |
| 216 | |
| 12\( \sqrt{9} \) |
To multiply terms with radicals, multiply the coefficients and radicands separately:
6\( \sqrt{4} \) x 6\( \sqrt{9} \)
(6 x 6)\( \sqrt{4 \times 9} \)
36\( \sqrt{36} \)
Now we need to simplify the radical:
36\( \sqrt{36} \)
36\( \sqrt{6^2} \)
(36)(6)
216
What is \( \frac{25\sqrt{12}}{5\sqrt{6}} \)?
| 5 \( \sqrt{\frac{1}{2}} \) | |
| 2 \( \sqrt{5} \) | |
| 5 \( \sqrt{2} \) | |
| \(\frac{1}{2}\) \( \sqrt{5} \) |
To divide terms with radicals, divide the coefficients and radicands separately:
\( \frac{25\sqrt{12}}{5\sqrt{6}} \)
\( \frac{25}{5} \) \( \sqrt{\frac{12}{6}} \)
5 \( \sqrt{2} \)