Tricks of Discount

Tricks....

1. Single discount equivalent to two successive discounts x% and y%
             = ( x + y - xy / 100)%

2. If a shopkeeper wants a profit of R% after allowing a discount of r%, then Marked Price(MP) of the item
             = CP{(100+R)/(100-r)}

3. If a shopkeeper allows a discount of y% on an article and marked price of the article is x% more than the cost price, then profit or loss per cent in this transaction
              = {x ×( 100- y) / 100} - y
     Note: Positive value shows a profit, while negative value shows loss.

Q. What will be a single equivalent discount for successive discounts of 10% and 5% on marked price of an article?
EXPLANATION Given x = 10%, y = 5%
Single equivalent discount = ( x + y - xy / 100)%
                                     = ( 10 + 5 - 10 × 5 / 100)%
                                     = 14.5 %

Q. The marked price of a bicycle is  1100. A shopkeeper allows a discount of 10% and get a profit of 10%. Find the cost price of the bicycle.
EXPLANATION
Here MP = 1100, r = 10%, R = 10%
According to the question,
              CP = MP {( 100 - r) /(100+R)}
                    = 1100 {(100- 10)/(100+10)}
                    = 1100 { 90/110}
                    = 900
Q. A shopkeeper marked the price 10% more than its cost price. If he allows a discount of 20%, then find his loss per cent.
EXPLANATION
 Here x = 10%, y = 20%
 According to the question,
           Loss or profit per cent ={ 10 ×(100-20) / 100} - 20
                              = 10× 80 / 100 - 20
                              = 8 - 20
                              = - 12
Therefore loss per cent = 12%

Q. If on a marked price, the difference of selling prices with a discount of 30% and two successive discounts of 20% and 10% is X 72, then find the marked price (in X).
EXPLANATION
Let the marked price = x
The discount equivalent to successive discounts 20% and 10% = (x + y - xy/100)%
where x = 20, y = 10
Then 30 - 2 = 28%
According to the question
    {(100- 28)x/100} - {(100-30)x/100} = 72
    x = 72 × 100 / 2 = 3600

Q. On a 20% discount sale, an article costs 596. What was the original price of the article?
EXPLANATION
Let the original price be x
At 20% discount,an article costs 596
Therefore
            596 = 80/ 100 × x
             x = 745
Therefore original price = 745

Tricks of Average

Tricks of Percentage 

Tricks of Divisibility


JOIN OUR TELEGRAM CHANNEL