Question

2.
The price of a house depreciates by 12.5% per annum. When the price was Rs. 80 lakh,
Rosesh invested a sum of Rs. 40 lakh at 12.5% per annum simple interest. What is the min-
imum number of years (integer value) that it will take for him to be able to buy the house
using his investment?




full explanation​

Answer 1

Step-by-step explanation:

SI =prt/100

SI = (4000000×12.5×t)/100

SI =500000t rs

8000000= 4000000+500000t

4000000=5000000t

t= 5000000÷4000000

t = 1yr 3 months

Answer 2

Answer:

answer is 2.9 yr approx 3yr

Step-by-step explanation:

house depreciate by 12.5% every year= (1-12.5/100) & for 'n' years because we don't know the years. solving above bracket ll get (7/8)^n

80lakh depreciate 7/8tines every year. where on the other side he has 40lakh a principal amount & the interest he ll get which is Simple interest.

i.e RHS will be Principal+Simple Interest

&SI= pnr/100

8000000(7/8)^n=4000000+(4000000*12.5*n/100)

8000000(7/8)^n=4000000+500000n

80(7/8)^n=5(n+8)

16(7/8)^n=(n+8)

LHS ll depreciate every year as increase in 'n' & for first (let's say x years LHS ll be greater than LHS)

for n=1

14>9

LHS>RHS

for n=2

12.25>10

LHS>RHS

for n=3

LHS<RHS

10.71<11

so it has to be less than 3 years

now put n= 2.9 yrs

LHS<RHS

put n= 2.8 yrs

LHS>RHS

hence 2.8 can't be the answer

therefore answer is it ll take 2.9yrs ~ (3yrs)