Aptitude - Simple Interest - Discussion
Discussion Forum : Simple Interest - General Questions (Q.No. 1)
1.
A sum of money at simple interest amounts to Rs. 815 in 3 years and to Rs. 854 in 4 years. The sum is:
Answer: Option
Explanation:
S.I. for 1 year = Rs. (854 - 815) = Rs. 39.
S.I. for 3 years = Rs.(39 x 3) = Rs. 117.
Principal = Rs. (815 - 117) = Rs. 698.
Discussion:
171 comments Page 5 of 18.
Suyash sonawane said:
7 years ago
3 year - 815,
4 year - 854,
4 yr - 3 yr= 854-815,
1 yr=39,
39*3=117,
Sum= 815-117= 698.
4 year - 854,
4 yr - 3 yr= 854-815,
1 yr=39,
39*3=117,
Sum= 815-117= 698.
(1)
Manisha Pal said:
6 years ago
We know,
Amount = Principe + interest.
4 year amount= principle + 4 year interest.
3 year amount = principle + 3 year interest.
Then,
39 = 1 year Interest.
Now to calculate principle or sum.
We have formula that, amount - interest.
4 year amount- 4-year interest
854-4*39 =698.
or 3 year amount - 3-year interest.
815-3*39=698.
Amount = Principe + interest.
4 year amount= principle + 4 year interest.
3 year amount = principle + 3 year interest.
Then,
39 = 1 year Interest.
Now to calculate principle or sum.
We have formula that, amount - interest.
4 year amount- 4-year interest
854-4*39 =698.
or 3 year amount - 3-year interest.
815-3*39=698.
(1)
Farru_faiz said:
6 years ago
P = sum.
SI = simple interest.
P+SI=815 ; P + SI=854
SI=815-P ; SI=854-P
SI=P*T*R/100
(815-P) =P*3*R/100 ------>1
(854-P) =P*4*R/100 ------>2
---- >>(1/2)
(815-p)/3 = (854-P)/4
(815-P)*4=3*(854-p)
3260-4P = 2562-3P
3260-2562 = 4 P-3P
698=P.
SI = simple interest.
P+SI=815 ; P + SI=854
SI=815-P ; SI=854-P
SI=P*T*R/100
(815-P) =P*3*R/100 ------>1
(854-P) =P*4*R/100 ------>2
---- >>(1/2)
(815-p)/3 = (854-P)/4
(815-P)*4=3*(854-p)
3260-4P = 2562-3P
3260-2562 = 4 P-3P
698=P.
(1)
Mahesh Narayankar said:
5 years ago
Let x=principal interest.
x+3*SI = 815.
x+4*Si = 854.
SI for 1 Year=854-815=39,
x+3*39=815,
x=815-117=698.
x+3*SI = 815.
x+4*Si = 854.
SI for 1 Year=854-815=39,
x+3*39=815,
x=815-117=698.
(1)
NIsha said:
5 years ago
Why we have subtracted 117 from 815 why not from 854?
(1)
V.malarvizhi said:
2 decades ago
Why not applied principal formula si*100/r*t ?
Jayesh said:
2 decades ago
Can the formula be SI*100/R*T ?
Kannan said:
1 decade ago
Why should not subsract with 854? Please clear my doubt....
Priya said:
1 decade ago
@Lavanya and kanna
To get 1 year difference we have to subtract
4year amount-3year amount
this difference amount is the 1 year simple interest..
that's why..
Rs. (854 - 815) = Rs. 39
39 is 1year S.I.
hope it helps you..
To get 1 year difference we have to subtract
4year amount-3year amount
this difference amount is the 1 year simple interest..
that's why..
Rs. (854 - 815) = Rs. 39
39 is 1year S.I.
hope it helps you..
Nag said:
1 decade ago
Thank you. This is explanation is very helpful for me.
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