Question

find the population of a city after 2 years which is at present 12 lakh , if the rate of increase is 4%.

Answer 1

HEY
HERE'S YOUR ANSWER!!

Present population = 12 lakh = 1200000
Time = 2 years
Rate of increase = 4%
Therefore, population after 2 years is
= present population(1 + r/100)²
= 1200000 (1 + 4/100)²
= 1200000 * (104/100)²
= 1200000 * 104/100 * 104/100
= 120 * 104 * 104
= 1297920. {ANSWER}

hope it helps!!

Answer 2

Formula is a =  p(1+r/100)^n             ------------------ (i)

Given p = 1200000, r = 4, n = 2

On submitting values in (i) we get, 

 a = 1200000(1+4/100)^2

    =  1200000(1 + 1/25)^2

    = 1200000(26/25)^2

    = 1200000 * 26/25 * 26/25

    = 1248000 * 26/25

    = 1297920


Hope this helps!