If apples are bought at the rate of 30 for a rupee. How many apples mu

Question

If apples are bought at the rate of 30 for a rupee. How many apples must be sold for a rupee so as to have a profit of 20%?

A. 36 
B. 28 
C. 26
D. 25 
E. 22

WhitEngagePrep · Accepted Answer

First, let's just make one note about the non-GMAT-like wording of the original question (that I think is actually very problematic). 
 
 I did a quick survey of some Official Guides and official practice question sources I have, and I have never seen the GMAT say profit of ____ without clearly specifying what you're taking that profit OF. In other words, the GMAT will always specify the "base." Some examples:

So without that information, I would look at this question and assume that it was experimental (or a poor quality non-official question). It is true that in finance textbooks, the implication is that a profit of 20% would be 20% on cost, so let's pretend that the question was more explicitly written to say that.

This question is a bit tricky because profit questions generally talk about the purchasing and selling prices directly. Here, you have to compute that (which lands you in ugly fractions).

Cost of an apple = 1/30th rupee

Since the "base" is cost, we need the sales price to be 20% greater than the cost.

Sales price of one apple = (120/100)(1/30) = (12/10)(1/30) = (6/5)(1/30) = 1/25th rupee.

Remember that this means that you need to sell 25 apples for 1 rupee! I highlighted in blue essentially what would be written on my paper!

:) 
 Whit

PKN · Answer

As the 20% profit is obtained, it implies that 30 apples were sold for 1(1+0.2)=Rs. 1.20 
So, SP of 1 apple= \frac{30}{1.20} =Rs. 0.04
Therefore, No of apples that would be sold in Rs1= \frac{1}{0.04} =25 nos

Ans. (D)

Archit3110 · Answer

30 apples are bought @ INR 1
so cost of 1 apple = 1/30
now selling apple to gain 20% of 1 INR would be SP= INR 1.2
so
we can say for every INR 1.2 of cost we would be having ; 1/1.2 = 0.83 of gain
since in 1 INR 30 apples were bought so to get 0.83 of gain we would have to sell
0.83 * 30 = 25 apples
IMO D

mt7777 · Answer

This question is basically asking for the costs in terms of apples.

First we need to find out the costs in rupees, if the sale price is 1 rupee and the margin 20%:
 1.2c=1 
 c=\frac{1}{1.2}=\frac{5}{6}

So the costs in apples, instead of rupees, would be:
 30*\frac{5}{6}=25

MartyTargetTestPrep · Answer

We bought 30 apples for 1 rupee.

We want a 20% profit when we sell a quantity of apples for 1 rupee.

Getting a 20% profit means we are paid 1.20 times, or 6/5, of what we spent.

So, 1 rupee has to be 6/5 of what we spent on the quantity of apples that we sell for 1 rupee.

So, to make that profit, would sell a quantity of apples that cost us 5/6 of a rupee: 5/6 x (the original lot of 30 apples) = 25 apples

The correct answer is D.

anmit123 · Answer

In real life,it is more like 30 rupees for an apple

Anyway, 1 rupee= 30 apples 20% profit ==> 30 apples should be sold for 1.2 rupees Now, 1.2 rupees = 30 apples ==> 1 rupee = 30/1.2 apples = 25 apples Ans:D

DrMock · Answer

@Bunuel I'm solving question of the like really slowly - is there some fundamental concept I'm not understanding? What can I do to improve here?

DiveshR · Answer

WhitEngagePrep ,  MartyTargetTestPrep ,  Bunuel

None of these solutions are making sense to me.

I set up my equation pretty straightforward: P/CP *100 = 20; (x-30)/30*100 = 20; x = 36.

Which makes sense because if we want to make more money, we'd have to sell more apples where SP = CP = 1 rupee.

I have fundamentally misunderstood something.

Edit: x is the number of apples sold for 1 rupee.

WhitEngagePrep · Answer

I'm not entirely sure what your different variables represent. Can you please confirm that you have set the following variables to mean the following things in your initial equation: P = Profit CP = Total Cost SP = Total Revenue x = number of apples sold for 1 rupee Without variables, I think that the equation you're going for is the following (total profit as a fraction of total cost given as a percent?) Total Profit ------------ x 100 = 20 Total Cost However, total Profit here isn't (x - 30). Profit needs a rupee amount and the units here are in numbers of apples. Your equation is: "Number of apples we sell for 1 rupee" - "Number of apples we bought for 1 rupee" --------------------------------------------------------------------------------------------- x 100 = 20 "Number of apples we bought for 1 rupee" If anything, this would translate to "the percent change in the number apples from what we bought to what we sold was a 20% increase". But this isn't the story in the question at all. You also say "to make more money, we'd have to sell more apples where SP = CP = 1 rupee," but now we run into two more logical problems. First , if SP = CP = 1 rupee, then I cannot be right about how you are defining these, because total cost and total revenue aren't 1 rupee. If they were, there would be a 0 profit. Second , in the way you (and the story) are defining x, we need to sell FEWER apples for 1 rupee in order to make money. Again, these is number of apples sold for 1 rupee total, not number of apples sold at 1 rupee apiece! Let's cheat and use a calculator so you can see why we need FEWER apples PER rupee From the question, we buy 30 apples for a rupee (sloppy but that means 1 rupee). So the cost per apple or rupees/apples = 1/30 =0.0333 rupees. That's what we PAID for each apple. So if we let x as you define it be 36, that means that we are going to sell apples for 36 APPLES PER 1 RUPEE. The price would then be 1/36 =0.0278 rupees per apple. If we paid 0.0333 for the apples and then sell them for 0.0278, we would be LOSING money. This is why this problem is so tricky. If you had a calculator, you could just do the division of 1/30 to get that each apple costs 0.0333 rupees. And in order to make a 20% profit on the cost, you'd just multiply 0.0333 * 1.2 in your calculator = 0.03996 and be able to check "YES, this is selling the apples for more than I made for them - I will definitely make a profit!" So again, I think the issue is a combo of vague and possibly changing definitions that you're using for your variables along with a mistranslation of Profit and Cost. Hope this helps!

Whit

ManishaPrepMinds · Answer

Why You’re Solving Slowly: 
Slowness in these questions usually comes from:
1.  Over-relying on formulas 
If you try to plug into formulas instead of thinking in terms of units, ratios, or logic, it slows you down.
2.  Missing the “per unit” insight 
For example:
“30 apples for Rs 1” = Rs 1/30 per apple
Many students overlook this simple unit shift, and get lost in over-complication.

How to Improve: 
Keep a Note of  Fast Patterns 
 
 x for Rs 1 → Rs 1/x per item 
  Profit% : 
→ SP = CP × (1 + profit%/100) 
  Loss% 
 → SP = CP × (1 − loss%/100)

Solution: 
CP = Rs 1 for 30 → Rs 1/30 per apple 
Want 20% profit
→ SP = 1.2 × CP = Rs 1/25 per apple 
So,  Sell 25 apples for Rs1

DiveshR · Answer

Thank you, Whit. I believe what confused me is "How many apples must be sold for a rupee" which I interpreted as how many apples must be sold at one rupee each ... which I know doesn't make sense since we'd have to sell more than we purchased. I think I just looked at it the wrong way and entirely confused myself.

luisdicampo · Answer

Deconstructing the Question

Apples are bought at the rate of  30 for 1 rupee . 
So the cost price of one apple is:

\frac{1}{30}

We need a  20% profit , so the selling price of one apple must be  120% of cost price .

Step-by-step

Cost price of 1 apple:

\frac{1}{30}

Selling price of 1 apple at 20% profit:

\frac{1}{30} 	imes 1.2

= \frac{1.2}{30}

= \frac{12}{300}

= \frac{1}{25}

So one apple must be sold for:

\frac{1}{25} 	ext{ rupee}

Therefore, for 1 rupee, the number of apples sold is:

25

Answer: 25

pappal · Answer

cost price of one apple =1/30 rupee
profit %=20%
so selling price of one apple=1.2*1/30=1/25 rupee
so for 1 rupee 25 apples must be sold to get the requisite profit.

If apples are bought at the rate of 30 for a rupee. How many apples mu

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If apples are bought at the rate of 30 for a rupee. How many apples mu

Prep Toolkit

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