| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.52 |
| Score | 0% | 70% |
If \( \left|b - 7\right| \) + 4 = 4, which of these is a possible value for b?
| -13 | |
| 7 | |
| -2 | |
| 9 |
First, solve for \( \left|b - 7\right| \):
\( \left|b - 7\right| \) + 4 = 4
\( \left|b - 7\right| \) = 4 - 4
\( \left|b - 7\right| \) = 0
The value inside the absolute value brackets can be either positive or negative so (b - 7) must equal + 0 or -0 for \( \left|b - 7\right| \) to equal 0:
| b - 7 = 0 b = 0 + 7 b = 7 | b - 7 = 0 b = 0 + 7 b = 7 |
So, b = 7 or b = 7.
Find the average of the following numbers: 17, 13, 19, 11.
| 17 | |
| 20 | |
| 16 | |
| 15 |
To find the average of these 4 numbers add them together then divide by 4:
\( \frac{17 + 13 + 19 + 11}{4} \) = \( \frac{60}{4} \) = 15
If a car travels 225 miles in 5 hours, what is the average speed?
| 45 mph | |
| 70 mph | |
| 55 mph | |
| 20 mph |
Average speed in miles per hour is the number of miles traveled divided by the number of hours:
speed = \( \frac{\text{distance}}{\text{time}} \)If the ratio of home fans to visiting fans in a crowd is 3:1 and all 34,000 seats in a stadium are filled, how many home fans are in attendance?
| 25,500 | |
| 31,500 | |
| 26,000 | |
| 29,600 |
A ratio of 3:1 means that there are 3 home fans for every one visiting fan. So, of every 4 fans, 3 are home fans and \( \frac{3}{4} \) of every fan in the stadium is a home fan:
34,000 fans x \( \frac{3}{4} \) = \( \frac{102000}{4} \) = 25,500 fans.
How many 15-passenger vans will it take to drive all 31 members of the football team to an away game?
| 6 vans | |
| 12 vans | |
| 8 vans | |
| 3 vans |
Calculate the number of vans needed by dividing the number of people that need transported by the capacity of one van:
vans = \( \frac{31}{15} \) = 2\(\frac{1}{15}\)
So, it will take 2 full vans and one partially full van to transport the entire team making a total of 3 vans.