Question 980507
In case of successive percentage change 'a' and 'b', the net percentage change is given by:


a + b + (a * b)/100


Here, a= -20; b= -30


Net percentage change= -20 + -30 + (-20 * -30)/100 = -50 + 6 = - 44

Net discount= 44 %


Second method:

20% discount is same as multiplying factor 0.80

30% discount is same as multiplying factor 0.70

Net multiplying factor = 0.80 * 0.70

=0.56

Multiplying factor is 0.56; thus the discount is 100 - 56 = 44%.


Thanks,
PRD
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