| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.04 |
| Score | 0% | 61% |
A sports card collection contains football, baseball, and basketball cards. If the ratio of football to baseball cards is 7 to 2 and the ratio of baseball to basketball cards is 7 to 1, what is the ratio of football to basketball cards?
| 5:8 | |
| 49:2 | |
| 3:4 | |
| 9:8 |
The ratio of football cards to baseball cards is 7:2 and the ratio of baseball cards to basketball cards is 7:1. To solve this problem, we need the baseball card side of each ratio to be equal so we need to rewrite the ratios in terms of a common number of baseball cards. (Think of this like finding the common denominator when adding fractions.) The ratio of football to baseball cards can also be written as 49:14 and the ratio of baseball cards to basketball cards as 14:2. So, the ratio of football cards to basketball cards is football:baseball, baseball:basketball or 49:14, 14:2 which reduces to 49:2.
If \( \left|b + 5\right| \) - 7 = -8, which of these is a possible value for b?
| 14 | |
| -2 | |
| -9 | |
| -6 |
First, solve for \( \left|b + 5\right| \):
\( \left|b + 5\right| \) - 7 = -8
\( \left|b + 5\right| \) = -8 + 7
\( \left|b + 5\right| \) = -1
The value inside the absolute value brackets can be either positive or negative so (b + 5) must equal - 1 or --1 for \( \left|b + 5\right| \) to equal -1:
| b + 5 = -1 b = -1 - 5 b = -6 | b + 5 = 1 b = 1 - 5 b = -4 |
So, b = -4 or b = -6.
What is 8b5 x 8b4?
| 64b-1 | |
| 64b20 | |
| 16b9 | |
| 64b9 |
To multiply terms with exponents, the base of both exponents must be the same. In this case they are so multiply the coefficients and add the exponents:
8b5 x 8b4
(8 x 8)b(5 + 4)
64b9
What is \( 6 \)\( \sqrt{175} \) + \( 6 \)\( \sqrt{7} \)
| 12\( \sqrt{7} \) | |
| 12\( \sqrt{175} \) | |
| 12\( \sqrt{1225} \) | |
| 36\( \sqrt{7} \) |
To add these radicals together their radicands must be the same:
6\( \sqrt{175} \) + 6\( \sqrt{7} \)
6\( \sqrt{25 \times 7} \) + 6\( \sqrt{7} \)
6\( \sqrt{5^2 \times 7} \) + 6\( \sqrt{7} \)
(6)(5)\( \sqrt{7} \) + 6\( \sqrt{7} \)
30\( \sqrt{7} \) + 6\( \sqrt{7} \)
Now that the radicands are identical, you can add them together:
30\( \sqrt{7} \) + 6\( \sqrt{7} \)What is the greatest common factor of 36 and 20?
| 2 | |
| 14 | |
| 4 | |
| 6 |
The factors of 36 are [1, 2, 3, 4, 6, 9, 12, 18, 36] and the factors of 20 are [1, 2, 4, 5, 10, 20]. They share 3 factors [1, 2, 4] making 4 the greatest factor 36 and 20 have in common.