| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.51 |
| Score | 0% | 70% |
Solve for \( \frac{3!}{5!} \)
| \( \frac{1}{56} \) | |
| 6 | |
| \( \frac{1}{3024} \) | |
| \( \frac{1}{20} \) |
A factorial is the product of an integer and all the positive integers below it. To solve a fraction featuring factorials, expand the factorials and cancel out like numbers:
\( \frac{3!}{5!} \)
\( \frac{3 \times 2 \times 1}{5 \times 4 \times 3 \times 2 \times 1} \)
\( \frac{1}{5 \times 4} \)
\( \frac{1}{20} \)
What is \( \frac{4}{8} \) + \( \frac{3}{12} \)?
| 1 \( \frac{8}{24} \) | |
| 2 \( \frac{6}{24} \) | |
| 1 \( \frac{3}{7} \) | |
| \(\frac{3}{4}\) |
To add these fractions, first find the lowest common multiple of their denominators. The first few multiples of 8 are [8, 16, 24, 32, 40, 48, 56, 64, 72, 80] and the first few multiples of 12 are [12, 24, 36, 48, 60, 72, 84, 96]. The first few multiples they share are [24, 48, 72, 96] making 24 the smallest multiple 8 and 12 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{4 x 3}{8 x 3} \) + \( \frac{3 x 2}{12 x 2} \)
\( \frac{12}{24} \) + \( \frac{6}{24} \)
Now, because the fractions share a common denominator, you can add them:
\( \frac{12 + 6}{24} \) = \( \frac{18}{24} \) = \(\frac{3}{4}\)
What is 2a2 x a4?
| 3a4 | |
| 3a2 | |
| 2a6 | |
| 2a8 |
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:
2a2 x a4
(2 x 1)a(2 + 4)
2a6
What is \( \frac{20\sqrt{12}}{4\sqrt{4}} \)?
| \(\frac{1}{5}\) \( \sqrt{3} \) | |
| 5 \( \sqrt{3} \) | |
| 3 \( \sqrt{\frac{1}{5}} \) | |
| 3 \( \sqrt{5} \) |
To divide terms with radicals, divide the coefficients and radicands separately:
\( \frac{20\sqrt{12}}{4\sqrt{4}} \)
\( \frac{20}{4} \) \( \sqrt{\frac{12}{4}} \)
5 \( \sqrt{3} \)
What is (b5)4?
| b-1 | |
| b20 | |
| b | |
| 4b5 |
To raise a term with an exponent to another exponent, retain the base and multiply the exponents:
(b5)4