

Get live Maths 1-on-1 Classs - Class 6 to 12
Examples
Example 1 (ii)
Example 1 (iii) Important
Example 2
Example 3 Important
Example 4
Example 5
Example 6 Important
Example 7 Important
Example 8
Example 9
Example 10 – GST (Page Number - 124)
Example 10 (Page no. 126) Important
Example 11
Example 12
Example 13 Important
Example 14 You are here
Example 15 Important
Last updated at March 23, 2023 by Teachoo
Example 14 The population of a city was 20,000 in the year 1997. It increased at the rate of 5% p.a. Find the population at the end of the year 2000. Population of city in 1997 = 20,000 It Increases at the Rate of 5% Per Annum Here, 5% is compounded Rate So we use the formula A = P (1+𝑅/100)^𝑛 Here, A = Population at end of 2000 P = Population in 1997 = 20,000 R = 5 % N = 2000 − 1997 = 3 Putting Values in Formula Population at end of 2000 = 20000 (1+5/100)^3 = 20000 (1+1/20)^3 = 20000 ((20 + 1)/20)^3 = 20000 (21/20)^3 = 20000 × (21 × 21 × 21)/(20 × 20 × 20) = (5 × 21 × 21 × 21)/2 = (441 × 21 × 5)/2 = (441 × 105)/2 = 46305/2 = 23152.5 Since population cannot be in decimals ∴ Estimated Population = 23,153