Aptitude - Profit and Loss - Discussion

@Chetan from where you got 1.2?

You can do even like this.

6 toffees for 1 rupee => 1 toffee for 1/6 rupees.

So to gain 20% profit.

Lets say he sells x toffees for 1 rupee => 1 toffee for 1/x rupees.

Now gain can be written as (1/x-1/6)/(1/6)*100.

This should be 20 (Easily make out here x is 5).

This is a good way for solving our problems related to maths.

6 CP = X SP

CP/SP = X/6

P% = {(X-6)/X}*100

25 = {(X-6)/X}*100

X = 5.

SP 6 toffee = 1.2 Rs(1 + 20% = 1.2).
Hence, SP of 1 Toffee = 1.2/6 = .2 Rs.

How many toffee need to be sold to get 1 rupee = .2 * 5 toffee = 1.

Short trick to know answer is:

6 * 100/120 = 5.

So 5, toffees in 1 Rupee to gain 20%.

Think logically for these sums.

You have 6 toffees for 1 Re.

Assume if he sells 3 toffees for 1 re his gain is 50%.

In this question, he needs 20% gain.

If he sells 5 toffies his gain will be 20%.

(if you still have doubt how he got 20% for 5 toffies).

Assume 6 toffies for 1 re=120% (this is total).

The Same manner see.

If he sells 1 toffee for 1 re his gains is 100%.

2 toffee for 1 re = 80%.
3toffee for 1 re = 60%.
4toffee for 1 re = 40%.
5toffee for 1re = 20%.

The more he sells for same amount gain reduce, the lesser no of toffees he sells for 1 re the gain increase.

I don't get the idea of how 6/5*6 is 5? Please help me. I am very weak in maths.

C.P. of 6 toffees = Re. 1
100 % = 1 Rs.
20 % of 1 Rs is = 0.2.

To make 1 Rs(C.P.) he has to sell = 0.2 * 5 = 1. Rs.

We have a gain of 1 Toffee means 20% gain on original cost Price after selling 5 toffees.

6 toffee = 1Rs cp
1 toffee = 1/6 Rs. cp

20% profit,so,
cp = 100.
sp = 120.

When cp is 100, sp is 120.
cp is 1, sp is 120/100,
cp is 1/6,sp is = 120/100.1/6,
= 1/5 rs.

Now, for 1/5 Rs = 1 toffee.
for 1rs = 5/1.1 = 5 toffees => answer.