Question

The price of tea is increase by 20% and hence the expenditure of a family increase by 10 % . find out by what percent the consumption has been decreased?
(short cut trick)

Answer 1

Solution Let price of tea and quantity of tea produced = 100P and 100Q respectively,
Then, monthly bill = 10000PQ.
Now,
⇒ Price of tea = 120P (After 20% increase)
⇒ Monthly bill = 11000PQ (after 10% increase)
Then, consumption = 11000PQ/120P = 1100Q/12 = 91.67Q
Reduction in Consumption = (100Q - 91.67Q)/100Q x 100%
= 8.33% or 25/3%