Question

1. In a country, the total income increased by 60% and
the population increased by 20% during a certain
period. Find the percentage increase in the per capita
income during that period.
(A) 25%
(B) 30%
(C) 33.33%
(D) 40%​

p.s. in such questions, can we not assume the population and income and solve? doing so gives a wrong answer..please help someone as to why cannot we assume the population and income to be some value and calculate then?

Answer 1

Answer:

c) 33.33% is the answer

Step-by-step explanation:

let x be the number of people

let y be the total income.

then per capita income will be y/x

population increases by 20%

so, new population= x+x*20/100

that will be equal to 120x/100

now, total income increases by 60%

New income will be = y+y*60/100

that will be equal to 160y/100

so, new per capita income= 160y/100 ÷ 120x/100

=160y/120x

=4y/3x

percapita income increases by= 4y/3x - y/x

=y/3x

increase in percentage= y/3x ÷ y/x *100

=1/3 *100

=33.33% option is c

ps. it is because the population or number of persons and total income may not be always same. in the question it is said that there is variation in population and income (20% and 60% respectively). Hope you have understood the problem