If during a one-day period the Q train arrives at the station 30% less

Question

If during a one-day period the Q train arrives at the station 30% less frequently than the B train, and the B train arrives 10% less frequently than the F train, then the Q train`s frequency is what percent of the F train`s frequency?

A. 27
B. 40
C. 60
D. 63
E. 90

A. 27
B. 40
C. 60
D. 63
E. 90

EgmatQuantExpert · Answer

Solution

Given:  
 • Train Q arrives 30% less frequently than train B
• Train B arrives 10% less frequently than train F

To find:  
 • Train Q’s frequency is what percent of train F’s frequency

Approach and Working:   
If we assume the frequency of train F as 100, then we can write
 • The frequency of train B = 100 * 0.9 = 90
• The frequency of train Q = 90 * 0.7 = 63

Hence, train Q’s frequency as a percentage of train F’s frequency =  \frac{63}{100} * 100  = 63%

Hence, the correct answer is option D.

Answer: D

LipiSinha · Answer

Let us assume that the frequency of train F is x. Then the frequency of train B is 9x/10.
Therefore, frequency of train Q is 70% of 9x/10 which is 63x/100.
Hence, the frequency of Q train is 63% of the frequency of train F.

The answer is D.

jp28 · Answer

Q=.7B 
 B=.9F 
 Q=.7(.9F) 
 Q=.63F

Ans = D

rakeshmishra5690 · Answer

q = 0.7b
b = 0.9f

% =  *100 = 0.43*100 = 63

Ans D

nkin · Answer

Frequency of Q in terms of F = 1*(1-0.3)*(1-0.1) = 1*0.7*0.9 = 0.63 or 63%

Option D

GMATinsight · Answer

Let, Frequency of Q = Q
Let, Frequency of B = B
Let, Frequency of F = F

Q = 0.7 B

and

B = 0.9 F

i.e. Q = 0.7*0.9F = 0.63F

i.e. Frequency of Q is 63% of frequency of train F

Answer: Option D

KarishmaB · Answer

This question just uses the concept of successive percentage changes.

F reduces by 10% and then further reduces by 30% to give Q.

F * (70/100)* (90/100) = Q

F * (63/100) = Q

So Q is 63% of F.

Answer (D)

ScottTargetTestPrep · Answer

We can create the equations:

Q = 0.7B

And

B = 0.9F

Substitute the second equation into the first, we have:

Q = 0.7(0.9F)

Q = 0.63F

Thus, the Q train’s frequency is 63 percent of the F train’s frequency.

Alternate Solution:

Let’s assume that the F train has 100 arrivals daily. The B train would then have (100)(0.9) = 90 arrivals, and the Q train would have (90)(0.7) = 63 arrivals. Thus, the Q train would have 63/100, or 63%, of the number of arrivals of the F train.

Answer: D

If during a one-day period the Q train arrives at the station 30% less

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If during a one-day period the Q train arrives at the station 30% less

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