Shortcut trick on profit and loss

Shortcut trick on profit and loss

The five most important question types asked in competitive exams with detailed explanation :

 1     If a man purchases a items for Rs.b and sells c items for Rs. D  then the gain or loss depending upon the +ve or –ve sign in final made by him is given by

                                                            

                Explanation:

                Cost price of the article: b/a

                Selling price of the article: d/c

                Profit : (d/c-b/a)*100/b/a  =   (ad-bc)*100/bc

2.      If a reduction of x% in the price of an article enables a person to buy n kg more for Rs. N then the original price per kg and new price of the item is given by

       

                Explanation:

                let Original selling price/Kg: Rs. P

Quantity bought in Rs N :N/P Kg

New selling price : P(100-x)/100

Quantity bought in new selling price : N*100/P(100-x)

Difference in the two quantities : n kg.

i.e   N/(100-x) –N*100/P(100-x) = n   (You can remember this eq. as well.)

on solving we get P : Rs. Nx/n(100-x) per kg.

new price : Rs. p(100-x)/100 per kg.

3.      If a person sells a goods at a profit of x% . Had he sold it at Rs.x more y% would have been gained then cost price is given by Rs

         

Explanation :

Let Org. cost price= Rs P

Then  selling price = Rs p*(100+x)/100

New selling price = Rs P*(100+y)/100

Difference in selling prices = Rs. X

P/100{y-x}=X  (Important equation)

P= X*100/(y-x)

4.      Cost price of x articles is equal to the selling price of y articles then profit % is given by

      

Explanation:

Cost Price*X=Selling Price*Y

Cost price/selling price=Y/X

Profit= (Xk-Yk)*100/Yk

Or profit= (x-y)*100/y

5.    A person buys certain quantity of an article for Rs a  . If he sells nth part of the stock at a loss of x% then to make an overall profit of y% on the total transaction he should sell the remaining stock at the % profit given by

         

Explanation:

Total cost price : Rs a

Total selling price required at profit of y%: a*(100+y)/100

Selling price of 1^st part : Rs na*(100-x)/100

Selling price of 2^nd part: (1-n)a*(100+p)/100    (let profit on 2^nd part :P)

Total selling price= selling price of 1^st part + selling price of 2^nd part

(100+y)=n*(100-x)+(1-n)*(100+p)

On solving we get profit on 2^nd part : (y+nx)/(1-n)%