| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.17 |
| Score | 0% | 63% |
Which of these numbers is a factor of 16?
| 2 | |
| 20 | |
| 13 | |
| 16 |
The factors of a number are all positive integers that divide evenly into the number. The factors of 16 are 1, 2, 4, 8, 16.
If \(\left|a\right| = 7\), which of the following best describes a?
none of these is correct |
|
a = -7 |
|
a = 7 or a = -7 |
|
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).
The total water usage for a city is 50,000 gallons each day. Of that total, 11% is for personal use and 23% is for industrial use. How many more gallons of water each day is consumed for industrial use over personal use?
| 6,000 | |
| 2,400 | |
| 12,000 | |
| 4,000 |
23% of the water consumption is industrial use and 11% is personal use so (23% - 11%) = 12% more water is used for industrial purposes. 50,000 gallons are consumed daily so industry consumes \( \frac{12}{100} \) x 50,000 gallons = 6,000 gallons.
Simplify \( \sqrt{20} \)
| 7\( \sqrt{10} \) | |
| 8\( \sqrt{5} \) | |
| 4\( \sqrt{5} \) | |
| 2\( \sqrt{5} \) |
To simplify a radical, factor out the perfect squares:
\( \sqrt{20} \)
\( \sqrt{4 \times 5} \)
\( \sqrt{2^2 \times 5} \)
2\( \sqrt{5} \)
This property states taht the order of addition or multiplication does not mater. For example, 2 + 5 and 5 + 2 are equivalent.
PEDMAS |
|
commutative |
|
distributive |
|
associative |
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.