Request a call back

Join NOW to get access to exclusive study material for best results

CBSE Class 7 Answered

Lily borrowed rupees 4000 from a friend at 5% for some years and return a sum of rupees 5200 by what time did he returned it
Asked by Cdpopiprali0 | 28 Jan, 2019, 20:04: PM
answered-by-expert Expert Answer
TYpe of interest , whether it is simple interest or interest compounded annualy, is not mentioned.
Answer is worked out for both the types.
 
Simple interest :-
 
Simple Interest I = (pnR)/100 , where p is principle amount, n is number of years, R is rate of interest
 
I = Rs.5200-Rs.4000 = Rs.1200
 
hence   (4000×n×5)/100 = 1200  or 200n = 1200  or n = 6 years.
 
Compound Interest :-
 
Amount A after n years is given by,    P[ 1 +(r/100) ]n = A
 
4000×[ 1+(5/100) ]n = 5200  or  ( 1.05 )n = 5200/4000 = 1.3
 
hence n×log(1.05) = log(1.3)
 
By solving the above eqn., we get n ≈ 5.4 years ≈ 5 years 5 months
Answered by Thiyagarajan K | 28 Jan, 2019, 20:45: PM
CBSE 7 - Maths
Asked by at6351341 | 22 Jul, 2024, 16:33: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 7 - Maths
Asked by rajnisurjeetyadav | 21 Jul, 2024, 11:27: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 7 - Maths
Asked by psat1975 | 19 Jul, 2024, 20:12: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 7 - Maths
Asked by richhariyavani | 13 Jul, 2024, 08:08: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 7 - Maths
Asked by aishahaveliwala31 | 07 Jul, 2024, 19:57: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 7 - Maths
Asked by rashisandeepnite | 02 Jul, 2024, 19:27: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 7 - Maths
Asked by greenindia112015 | 28 Jun, 2024, 20:58: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 7 - Maths
Asked by yadavnilam715 | 26 Jun, 2024, 17:32: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 7 - Maths
Asked by lohithkumar577 | 19 Jun, 2024, 18:57: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
Are You a Teacher or a Parent Seeking Customised Tests? Click here
×