| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.00 |
| Score | 0% | 60% |
Find the average of the following numbers: 15, 13, 18, 10.
| 11 | |
| 12 | |
| 14 | |
| 18 |
To find the average of these 4 numbers add them together then divide by 4:
\( \frac{15 + 13 + 18 + 10}{4} \) = \( \frac{56}{4} \) = 14
| 3.0 | |
| 1 | |
| 3.5 | |
| 6.3 |
1
What is \( \frac{2x^8}{9x^4} \)?
| \(\frac{2}{9}\)x2 | |
| \(\frac{2}{9}\)x\(\frac{1}{2}\) | |
| \(\frac{2}{9}\)x32 | |
| \(\frac{2}{9}\)x4 |
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:
\( \frac{2x^8}{9x^4} \)
\( \frac{2}{9} \) x(8 - 4)
\(\frac{2}{9}\)x4
The total water usage for a city is 40,000 gallons each day. Of that total, 30% is for personal use and 55% is for industrial use. How many more gallons of water each day is consumed for industrial use over personal use?
| 8,000 | |
| 10,000 | |
| 9,800 | |
| 4,000 |
55% of the water consumption is industrial use and 30% is personal use so (55% - 30%) = 25% more water is used for industrial purposes. 40,000 gallons are consumed daily so industry consumes \( \frac{25}{100} \) x 40,000 gallons = 10,000 gallons.
If all of a roofing company's 4 workers are required to staff 2 roofing crews, how many workers need to be added during the busy season in order to send 5 complete crews out on jobs?
| 9 | |
| 1 | |
| 6 | |
| 13 |
In order to find how many additional workers are needed to staff the extra crews you first need to calculate how many workers are on a crew. There are 4 workers at the company now and that's enough to staff 2 crews so there are \( \frac{4}{2} \) = 2 workers on a crew. 5 crews are needed for the busy season which, at 2 workers per crew, means that the roofing company will need 5 x 2 = 10 total workers to staff the crews during the busy season. The company already employs 4 workers so they need to add 10 - 4 = 6 new staff for the busy season.