| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.17 |
| Score | 0% | 63% |
a(b + c) = ab + ac defines which of the following?
commutative property for multiplication |
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distributive property for multiplication |
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commutative property for division |
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distributive property for division |
The distributive property for multiplication helps in solving expressions like a(b + c). It specifies that the result of multiplying one number by the sum or difference of two numbers can be obtained by multiplying each number individually and then totaling the results: a(b + c) = ab + ac. For example, 4(10-5) = (4 x 10) - (4 x 5) = 40 - 20 = 20.
If a rectangle is twice as long as it is wide and has a perimeter of 6 meters, what is the area of the rectangle?
| 8 m2 | |
| 162 m2 | |
| 2 m2 | |
| 98 m2 |
The area of a rectangle is width (w) x height (h). In this problem we know that the rectangle is twice as long as it is wide so h = 2w. The perimeter of a rectangle is 2w + 2h and we know that the perimeter of this rectangle is 6 meters so the equation becomes: 2w + 2h = 6.
Putting these two equations together and solving for width (w):
2w + 2h = 6
w + h = \( \frac{6}{2} \)
w + h = 3
w = 3 - h
From the question we know that h = 2w so substituting 2w for h gives us:
w = 3 - 2w
3w = 3
w = \( \frac{3}{3} \)
w = 1
Since h = 2w that makes h = (2 x 1) = 2 and the area = h x w = 1 x 2 = 2 m2
How many hours does it take a car to travel 300 miles at an average speed of 50 miles per hour?
| 6 hours | |
| 2 hours | |
| 3 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 = \( \frac{300mi}{50mph} \)
6 hours
Diane scored 76% on her final exam. If each question was worth 2 points and there were 100 possible points on the exam, how many questions did Diane answer correctly?
| 38 | |
| 48 | |
| 30 | |
| 35 |
Diane scored 76% on the test meaning she earned 76% of the possible points on the test. There were 100 possible points on the test so she earned 100 x 0.76 = 76 points. Each question is worth 2 points so she got \( \frac{76}{2} \) = 38 questions right.
If all of a roofing company's 12 workers are required to staff 3 roofing crews, how many workers need to be added during the busy season in order to send 5 complete crews out on jobs?
| 17 | |
| 1 | |
| 8 | |
| 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 12 workers at the company now and that's enough to staff 3 crews so there are \( \frac{12}{3} \) = 4 workers on a crew. 5 crews are needed for the busy season which, at 4 workers per crew, means that the roofing company will need 5 x 4 = 20 total workers to staff the crews during the busy season. The company already employs 12 workers so they need to add 20 - 12 = 8 new staff for the busy season.