Question

hypothetically speaking since 1951 onwards India's population is increasing at the rate of 12 crore every decade. if according to 1951 census India's population was 37 crores. by using arithmetic progression find out what was the population in 1991 and will be estimated population in 2031

Answer 1

The estimated population of India will be 145 crores. Because 9 decades separate 1951 and 2031. 12 x 9 equal 108 crores. Since in 1951 India's population was 37 crores, we have to add 108 and 37 to get the answer.