| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.12 |
| Score | 0% | 62% |
Solve for \( \frac{2!}{6!} \)
| \( \frac{1}{360} \) | |
| \( \frac{1}{6720} \) | |
| 336 | |
| \( \frac{1}{8} \) |
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:
\( \frac{2!}{6!} \)
\( \frac{2 \times 1}{6 \times 5 \times 4 \times 3 \times 2 \times 1} \)
\( \frac{1}{6 \times 5 \times 4 \times 3} \)
\( \frac{1}{360} \)
How many hours does it take a car to travel 280 miles at an average speed of 70 miles per hour?
| 3 hours | |
| 7 hours | |
| 2 hours | |
| 4 hours |
Average speed in miles per hour is the number of miles traveled divided by the number of hours:
speed = \( \frac{\text{distance}}{\text{time}} \)Solving for time:
time = \( \frac{\text{distance}}{\text{speed}} \)
time = \( \frac{280mi}{70mph} \)
4 hours
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 $50, how much will he pay for both shirts?
| $25.00 | |
| $70.00 | |
| $75.00 | |
| $55.00 |
By buying two shirts, Roger will save $50 x \( \frac{50}{100} \) = \( \frac{$50 x 50}{100} \) = \( \frac{$2500}{100} \) = $25.00 on the second shirt.
So, his total cost will be
$50.00 + ($50.00 - $25.00)
$50.00 + $25.00
$75.00
What is \( \frac{5}{6} \) - \( \frac{9}{8} \)?
| -\(\frac{7}{24}\) | |
| 2 \( \frac{8}{13} \) | |
| 2 \( \frac{2}{9} \) | |
| \( \frac{6}{24} \) |
To subtract these fractions, first find the lowest common multiple of their denominators. The first few multiples of 6 are [6, 12, 18, 24, 30, 36, 42, 48, 54, 60] and the first few multiples of 8 are [8, 16, 24, 32, 40, 48, 56, 64, 72, 80]. The first few multiples they share are [24, 48, 72, 96] making 24 the smallest multiple 6 and 8 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{5 x 4}{6 x 4} \) - \( \frac{9 x 3}{8 x 3} \)
\( \frac{20}{24} \) - \( \frac{27}{24} \)
Now, because the fractions share a common denominator, you can subtract them:
\( \frac{20 - 27}{24} \) = \( \frac{-7}{24} \) = -\(\frac{7}{24}\)
Which of the following statements about exponents is false?
b1 = 1 |
|
b0 = 1 |
|
b1 = b |
|
all of these are false |
A number with an exponent (be) consists of a base (b) raised to a power (e). The exponent indicates the number of times that the base is multiplied by itself. A base with an exponent of 1 equals the base (b1 = b) and a base with an exponent of 0 equals 1 ( (b0 = 1).