UPSC CDS Math Profit and Loss Questions

Single equivalent discount on successive discounts of 10% and Single equivalent discount on successive discounts of 28% and
40%=(28+40−

28×40

100

)%
=56.8%
Thus, the value of a single discount that is equivalent to a series of discounts of 10%, 20% and 40% is 56.8%
Trick :
Required single discount
=100[1−

9

10

×

4

5

×

3

5

]
=100×0.568=56.8