A diner adds a tip of 20% to his dinner bill. If he pays a total of $9

Question

A diner adds a tip of 20% to his dinner bill. If he pays a total of $90 for the bill and tip, how much less would he have paid if he had tipped 15% instead of 20%?

(A)  $3.75

(B)  $4.50

(C)  $5.00

(D)  $11.25

(E)  $13.50

prabsahi · Answer

Let d be the dinner bill.So tip is 0.20d

Total Bill paid= 1.20d

Now 1.2d = 90
 d=90/1.2 = 75

Tip paid when rate is 20%= 0.20d = 15

Now when tip is 15% ,tip paid = .15*75= 7.5+ 3.75(10% of 15 + 5% of 15 for quick calculation) = 11.25

Therefore net tip which was paid less = 15 - 11.25= 3.75

So I guess option A is correct.

Press Kudos if it helps!!

Abhishek009 · Answer

90/120*(120 - 115)

= 3.75, Answer must be (A)

Archit3110 · Answer

meal amount ; 90/1.2= 75$ 
75*1.15= 86.25
more he paid ' 90-86.25= 3.75
IMO A

ScottTargetTestPrep · Answer

Letting b = the meal cost before the tip, we can create the equation:

1.2b = 90

b = 75

So, if there was a 15% tip, the total would have been 1.15 x 75 = $86.25, so the diner would have paid 90 - 86.25 = $3.75 less.

Answer: A

A diner adds a tip of 20% to his dinner bill. If he pays a total of $9

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Problem Solving (PS) Questions

A diner adds a tip of 20% to his dinner bill. If he pays a total of $9

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards