| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.54 |
| Score | 0% | 71% |
What is -7c7 x 5c3?
| -2c10 | |
| -35c7 | |
| -35c4 | |
| -35c10 |
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:
-7c7 x 5c3
(-7 x 5)c(7 + 3)
-35c10
Which of the following is an improper fraction?
\({7 \over 5} \) |
|
\({2 \over 5} \) |
|
\({a \over 5} \) |
|
\(1 {2 \over 5} \) |
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.
4! = ?
4 x 3 |
|
5 x 4 x 3 x 2 x 1 |
|
3 x 2 x 1 |
|
4 x 3 x 2 x 1 |
A factorial has the form n! and is the product of the integer (n) and all the positive integers below it. For example, 5! = 5 x 4 x 3 x 2 x 1 = 120.
A machine in a factory has an error rate of 9 parts per 100. The machine normally runs 24 hours a day and produces 8 parts per hour. Yesterday the machine was shut down for 4 hours for maintenance.
How many error-free parts did the machine produce yesterday?
| 144 | |
| 145.6 | |
| 129 | |
| 86.5 |
The hourly error rate for this machine is the error rate in parts per 100 multiplied by the number of parts produced per hour:
\( \frac{9}{100} \) x 8 = \( \frac{9 \times 8}{100} \) = \( \frac{72}{100} \) = 0.72 errors per hour
So, in an average hour, the machine will produce 8 - 0.72 = 7.28 error free parts.
The machine ran for 24 - 4 = 20 hours yesterday so you would expect that 20 x 7.28 = 145.6 error free parts were produced yesterday.
Alex loaned Charlie $1,500 at an annual interest rate of 2%. If no payments are made, what is the interest owed on this loan at the end of the first year?
| $8 | |
| $63 | |
| $30 | |
| $18 |
The yearly interest charged on this loan is the annual interest rate multiplied by the amount borrowed:
interest = annual interest rate x loan amount
i = (\( \frac{6}{100} \)) x $1,500
i = 0.02 x $1,500
i = $30