| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.35 |
| Score | 0% | 67% |
Which of the following is a mixed number?
\({7 \over 5} \) |
|
\({5 \over 7} \) |
|
\({a \over 5} \) |
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\(1 {2 \over 5} \) |
A rational number (or fraction) is represented as a ratio between two integers, a and b, and has the form \({a \over b}\) where a is the numerator and b is the denominator. An improper fraction (\({5 \over 3} \)) has a numerator with a greater absolute value than the denominator and can be converted into a mixed number (\(1 {2 \over 3} \)) which has a whole number part and a fractional part.
If \(\left|a\right| = 7\), which of the following best describes a?
a = -7 |
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a = 7 or a = -7 |
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a = 7 |
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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).
Convert z-3 to remove the negative exponent.
| \( \frac{1}{z^3} \) | |
| \( \frac{-1}{-3z^{3}} \) | |
| \( \frac{-3}{z} \) | |
| \( \frac{-1}{z^{-3}} \) |
To convert a negative exponent to a positive exponent, calculate the positive exponent then take the reciprocal.
What is \( \frac{4x^7}{8x^4} \)?
| \(\frac{1}{2}\)x3 | |
| \(\frac{1}{2}\)x1\(\frac{3}{4}\) | |
| 2x-3 | |
| 2x11 |
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:
\( \frac{4x^7}{8x^4} \)
\( \frac{4}{8} \) x(7 - 4)
\(\frac{1}{2}\)x3
A menswear store is having a sale: "Buy one shirt at full price and get another shirt for 50% off." If Roger buys two shirts, each with a regular price of $33, how much will he pay for both shirts?
| $16.50 | |
| $39.60 | |
| $49.50 | |
| $46.20 |
By buying two shirts, Roger will save $33 x \( \frac{50}{100} \) = \( \frac{$33 x 50}{100} \) = \( \frac{$1650}{100} \) = $16.50 on the second shirt.
So, his total cost will be
$33.00 + ($33.00 - $16.50)
$33.00 + $16.50
$49.50