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
-
Q #1: Which of the following weights is equivalent to 3.193 kilograms?
A. 3,193,000 grams
B. 3,193 grams
C. 319.3 grams
D. 0.003193 grams
Answer Explanation
We use the relation 1 kg=1000 g to convert 3.193 kg to g
-
Q #2: Two friends get frozen yoghurt. The ratio of yoghurt to toppings is 4:3. If one of the friends has 4.5 oz of toppings in their bowl, which of the following is the amount of yoghurt in their desert?
A. 6 oz
B. 5.5 oz
C. 3 oz
D. 3.5 oz
Answer Explanation
Yoghurt: toppings=4:3
Yoghurt: 4.5 oz =4:3
We convert the given ratio into a proportion equation as below
Multiply both sides by 4.5 oz
-
Q #3: 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
