Advertisements
Advertisements
प्रश्न
The population of a town was decreasing every year due to migration, poverty and unemployment. The present population of the town is 6,31,680. Last year the migration was 4% and the year before last, it was 6%. What was the population two years ago?
Advertisements
उत्तर
Let the population two years ago = P (Principal)
Present population of the town = A = 631680
Rate of migration in 1st year = 4%
Rate of migration in 2nd year = 6%
By using the formula,
`A = P(1 - R/100)(1 - R/100)`
⇒ `631680 = P(1 - 4/100)(1 - 6/100)`
⇒ `631680 = P xx 24/25 xx 47/50`
⇒ `P = (631680 xx 25 xx 50)/(24 xx 47)`
⇒ P = 560 × 1250 = 700000
Hence, the population of town was 700000 two years ago.
APPEARS IN
संबंधित प्रश्न
The population of a place increased to 54000 in 2003 at a rate of 5% per annum Find the population in 2001.
A scooter was bought at Rs 42,000. Its value depreciated at the rate of 8% per annum. Find its value after one year.
Find the compound interest on Rs 160000 for one year at the rate of 20% per annum, if the interest is compounded quarterly.
The compound interest on Rs 1800 at 10% per annum for a certain period of time is Rs 378. Find the time in years.
The population of a city increases each year by 4% of what it had been at the beginning of each year. If the population in 1999 had been 6760000, find the population of the city in (i) 2001 (ii) 1997
The population of a city increases each year by 4% of what it had been at the beginning of each year. If the population in 1999 had been 6760000, find the population of the city in (i) 2001 (ii) 1997.
.
Pritam bought a plot of land for Rs 640000. Its value is increasing by 5% of its previous value after every six months. What will be the value of the plot after 2 years?
The value of a refrigerator which was purchased 2 years ago, depreciates at 12% per annum. If its present value is Rs 9680, for how much was it purchased?
Sameerrao has taken a loan of ₹ 12500 at a rate of 12 p.c.p.a. for 3 years. If the interest is compounded annually, then how many rupees should he pay to clear his loan?
On the construction work of a flyover bridge there were 320 workers initially. The number of workers were increased by 25% every year. Find the number of workers after 2 years.
A principal amounts to ₹ 13,924 in 2 years by compound interest at 18 p.c.p.a. Find the principal.
