| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.33 |
| Score | 0% | 67% |
What is the next number in this sequence: 1, 3, 7, 13, 21, __________ ?
| 31 | |
| 37 | |
| 30 | |
| 36 |
The equation for this sequence is:
an = an-1 + 2(n - 1)
where n is the term's order in the sequence, an is the value of the term, and an-1 is the value of the term before an. This makes the next number:
a6 = a5 + 2(6 - 1)
a6 = 21 + 2(5)
a6 = 31
Which of the following is not a prime number?
9 |
|
7 |
|
2 |
|
5 |
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.
If \(\left|a\right| = 7\), which of the following best describes a?
a = -7 |
|
a = 7 or a = -7 |
|
a = 7 |
|
none of these is correct |
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).
What is \( \frac{1}{7} \) x \( \frac{4}{6} \)?
| \(\frac{2}{21}\) | |
| \(\frac{2}{27}\) | |
| \(\frac{2}{63}\) | |
| \(\frac{2}{45}\) |
To multiply fractions, multiply the numerators together and then multiply the denominators together:
\( \frac{1}{7} \) x \( \frac{4}{6} \) = \( \frac{1 x 4}{7 x 6} \) = \( \frac{4}{42} \) = \(\frac{2}{21}\)
What is \( \frac{9a^5}{2a^3} \)?
| 4\(\frac{1}{2}\)a15 | |
| \(\frac{2}{9}\)a2 | |
| 4\(\frac{1}{2}\)a2 | |
| \(\frac{2}{9}\)a-2 |
To divide terms with exponents, the base of both exponents must be the same. In this case they are so divide the coefficients and subtract the exponents:
\( \frac{9a^5}{2a^3} \)
\( \frac{9}{2} \) a(5 - 3)
4\(\frac{1}{2}\)a2