The daytime telephone rate between two cities is 60 cents for the firs

So initially I agree with you but in the answer choice it is not "32c", it is 0.32c, which I believe ruins that answer choice? I am not sure but especially since the answer is meant to be given in dollars. Looking forward to the explanation!

I think the solution might be to choose a value for C and plug in to the answer choices. Which I will do now...

EDIT!!!!!!

Forget what I wrote haha. I realize that changing it to 0.32c is accounting for the fact that the answer is meant to be in dollars and not cents I just got very confused !

I agree with answer choice B

Hi All,

These types of PS questions can be solved with Algebra or by TESTing VALUES.

We're told that the cost of a daytime phone call is 60 CENTS for the first 3 minutes and C CENTS for each additional minute. We're also told that the total charge is reduced 60 percent on calls made after 10:00 P.M. We're asked for the cost, in DOLLARS, of a 35-minute call made at 10:30 P.M.

IF....
C = 10
The daytime cost of a 35-minute call is $0.60 + 32($0.10) = $3.80
The nighttime cost of this call is reduced 60%.....
$3.80 - (.6)($3.80) = (.4)($3.80) = $1.44

Answer A = 0.4(0.60) + 35c = .24 + 350 = 350.24 NOT a match
Answer B = 0.4(0.60 + 0.32c) = .4(3.80) = 1.44 This IS a match
Answer C = 0.4(0.60 + 9c) = .4(90.6) = 36.24 NOT a match
Answer D = 0.6(0.60 + 32c) = .6(320.6) = TOO big; NOT a match
Answer E = 0.6(0.60 + 0.35c) = .6(4.1) = 2.46 NOT a match

Final Answer:

GMAT assassins aren't born, they're made,
Rich

Charge for 35 mins of call \(=\,first\,3\,mins\,+\,32mins\,=\,0.60\,+\,32\frac{c}{100}\)

Since the call was made after 10:00, the total charge was reduced by 60% i.e. pay 40% of the total charge

Total Charge \(=\,0.4(\,0.60\,+\,0.32c)\)

Answer B

The call was made at 10:30 pm and lasted till 11:05 pm

Charge for the first 3 minutes=60 cents=$0.60
Charge for the next 32 minutes=$(c/100)*32
Total Charge=40%(0.60+0.32c)
Answer B

Price is 0.6 for the first 3 minutes

Remaining minutes is 35-3=32, thus, the price for the remaining 32 minutes would be 32c when looking at this in a dollar ammount we must divide by 100 giveing us 0.32c.

Non discounted price for the call would be 0.6+0.32c.

A 60% discount gives us the multiplier of 0.6 so to find the price we must subtract the multiplier from 1. 1-0.6=0.4

The discounted price is applied to the entire call since it occurs after 10PM giving us,

0.4(0.6+0.32c) select answer choice B.

VERITAS PREP OFFICIAL SOLUTION:

Though this is not the only way to approach this problem, a good way to start is to plug in some real numbers so that we don’t have to conceptualize what this equation does. We could, solely based on our knowledge of how these kinds of equations are formed, construct the equation we desire, but we can also attempt to use real numbers to elucidate which answer choice makes sense. Let’s imagine you are charged 10 cents per minute after the first three minutes (c =10 ). If you made a thirty five minute phone call, you would be charged $0.60 for three minutes, and then ($0.10)(32) for the next 32 minutes giving a total cost of $3.80 for the call.

That whole number is reduced by 60% because the call is after 10pm. Does that mean I multiply $3.80 by 0.6? If I did, the result would be 2.28, but 60% is more than half, so a reduction of 60% would make a number smaller than 3.8(0.5) or 1.9. This makes it clear that reducing by a percentage is different from multiplying by a percentage. If I reduce by 60%, I am actually taking 60% away, which leaves me with 40%, so my final answer will be $3.80(0.4) = $1.52. Now, all I have to do is plug in 10 for c and in all the equations and see which on gives me 1.52, which will be answer choice (B).

60cent for the first 3 minutes and c cents for each additional minute
The total charge is reduced 60 percent on calls made after 10:00 P.M. -> I have to pay the 40%
The cost, in dollars, of a 35-minute call made at 10:30 P.M. between these two cities is:
0.4(0.60 (first 3 min)+32c)

Answer B

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