Advertisements
Advertisements
प्रश्न
There is a continuous growth in population of a village at the rate of 5% per annum. If its present population is 9,261, what population was 3 years ago?
Advertisements
उत्तर
Let P be the population 3 years ago.
Then, present population = P x `(1 + 5/100)^3`
∴ 9,261 = `("P" xx (21)/(20) xx (21)/(20) xx (21)/(20))`
or P = `(9,261 xx (20)/(21) xx (20)/(21) xx (20)/(21))`
= 8,000
Hence, 3years ago the population of village was = 8,000.
संबंधित प्रश्न
Mr Kumar borrowed Rs. 15000 for two years. The rates of interest for two successive years are 8% and 10% respectively. If he repays Rs. 6200 at the end of the first year, find the outstanding amount at the end of the second year.
Alisha invested Rs 75000 for 4 years at 8 % p.a. compound interest ,
Find the amount at the end of third year.
Aryan borrowed a sum or Rs. 36,000 for `1 1/2` years at 10 % p.a. compound interesL
Find he tol interest paid by him.
Harijyot deposited Rs 27500 in a deposite scheme paying 12 % p.a. compound interest . If the duration of the deposite is 3 years , calculate :
The amount received by him at the end of three years.
Prerna borrowed Rs.16000 from a friend at 15 % p.a. compound interest. Find the amount , to the nearest rupees, that she needs to return at the end of 2.4 years to clear the debt.
Archana borrowed Rs 18,000 from Ritu at 12% p.a. compound interest. If at the end of the 1st, 2nd, and 3rd years, Archana returned Rs 5,250, Rs 5,875 and Rs 6,875 respectively, find the amount Archana has to pay Ritu at the end of the 4th year to clear her debt.
A man's savings increases by Rs 50 every year. If he saves Rs 500 in the first year and puts it at 10% compound interest, find his savings at the end of the third year.
Calculate the amount and the compound interest on:
Rs. 8,000 in `2 1/2` years at 15% per year.
Find the compound interest, correct to the nearest rupee, on Rs. 2,400 for `2 1/2` years at 5 per cent per annum.
6000 workers were employed to construct a river bridge in four years. At the end of first year, 20% workers were retrenched; At the end of second year 5% of the workers at that time were retrenched. However, to complete the project in time, the number of workers was increased by 15% at the end of third year. How many workers were working during the fourth year?
