Home » Aptitude » Discount » Question
  1. A single discount equivalent to the series of discounts 20%, 10% and 5% is equal to :
    1. 32%
    2. 30%
    3. 30.7%
    4. 31.6%
Correct Option: D

Single equivalent discount for x% and y%.

= x + y −
xy
%
100

∴  Single equivalent discount for 20% and 10%
= 20 + 10 −
20 × 10
% = 28%
100

Single equivalent discount for 28% and 5%
= 28 + 5 −
28 × 5
%
100

= 33 −
140
%
100

= (33 – 1.4)% = 31.6%
2nd Method to solve this question :
According to given question.
D1 = 20%, D2 = 10%, D3 = 5%
Single equivalent discount
= 100 −
100 − D1
100 − D2
100 − D3
× 100
100100100

= 100 −
100 − 20
100 − 10
100 − 5
× 100
100100100

= 100 −
80
×
90
×
95
× 100
100100100

= 31.6%



Your comments will be displayed only after manual approval.