A homeowner has hired two people to mow his lawn. If person A is able to mow the lawn in 2 hr by herself and person B is able to mow in lawn in 3 hr by himself. Which of the following is the amount of time it would take for both person A and B to mow the lawn together?
A. 5 hours
B. 2.5 hours
C. 1.2 hours
D. 1 hours
We know that the two people work on the same work but the time to complete the work differs. Thus, the rate of doing the work for each person is as follows:
Rate of work for person A = 1 /2 work per hr
Rate of work for person B=1/3 work per hour
If person A and B work together, the time of doing the same work will be less than the fastest person A. Thus, we combine the two rates of A and B
We have 1 work and time to complete by both A and B becomes
Therefore, the Correct Answer is C.
More Questions on TEAS 7 Math
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Q #1: A soccer field is rectangular in shape and is 100 meters long and 75 meters wide. The hectare is a metric unit of are often used to measure larger areas. Given that 1 hectare = 10000 meters2, which of the following represents the soccer field’s are in hectares?
A. 0.75 hectares
B. 7.5 hectares
C. 7,500 hectares
D. 75,000,000 hectares
Answer Explanation
The dimension of the field is shown below.
Area of rectangle = length * width
Area of rectangle = 100 m *75 m = 7500 m2
Area of the rectangle in hectares =
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Q #2: The force applied is directly proportional to the stretch of a coil. If a force of 132 Newtons stretches a coil 0.07 meters, what force would be needed to stretch a coil 0.1 meter? Round your answer to the nearest tenth.
A. 92.4 Newtons
B. 1885.7 Newtons
C. 188.6 Newtons
D. 136.0 Newtons
Answer Explanation
In direct proportion relation, we utilize the relationship as:
Variable∝
Variable 2Thus from the given case,
Force∝
stretchWe introduce a constant term, K to remove the sign of proportionality as
Force=K* stretch
Let’s find the value of K, using Force=132 N and stretch of 0.07 m
132 N=K*0.07 m
K=132 N/0.07 m=1885.7 N/m
Now substitute this value of K in the following equation
Force=1885.7 N/m * stretch
For a stretch of 0.1 m, the force needed is
Force=1885.7 N/m * 0.1 m=188.57 N=188.6 N
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Q #3: A consumer recently purchased a new car and paid $48,000. This amount is $2,000 less than twice what the consumer’s friend paid for their car. Which of the following is the amount that the friend paid for their car?
A. $23,000
B. $46,000
C. $25,000
D. $50,000
Answer Explanation
Let the amount the friend pays be x. Then, 2 times what the friend pays is 2x. Less $2,000 what the friend pays is 2x-2000.
Now we know that
2x-2000=48000
Add 2000 to both sides of the equation
2x-2000+2000=48000+2000
2x+2000-2000=50000
2x=50000
Divide both sides by 2
X=25000
Thus, the friend pays $25,000 for their car.
