There is 40% increase in an amount in 8 years at simple interest. What will be the compound interest

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24 Jan 2017 Interest

There is 40% increase in an amount in 8 years at simple interest. What will be the compound interest of Rs. 1,600 after 3 years at the same rate?

OPtion

1) Rs. 242.5
2) Rs. 244.2
3) Rs. 248.5
4) Rs. 252.2
5) Rs. 256.5
6) Rs. 260.2
7) Rs. 264.5
8) Rs. 268.2
9) Rs. 272.5
10)Rs. 276.2

Solution

Let investment in 1st case be Rs. 100, then SI= Rs. 140
Rate = 100*40/(100*8) = 5%
CI= P (1 + r/100) ^T – P
=1600 * (1+0.05)^3 ) – 1600 = 1852.2 – 1600 = 252.2

Option 4)

Correct Option: 4 Best Solution (25)

G.S.Kantharao   7 years AGO

I=PTR/100
1600*40/100=1600*8*R/100
R=5%
A=P(1+R/100)³
=1600{1+(5/100)}³
=1600(1.05)³=1852.2
Compound Interest = 252.2
Hence it is 4 to choose.

Like? Yes (4) | No   

Devendra Marghade   7 years AGO

Let the amount be x, then
S.I. in 8 years at the rate of r% = x*8*r/100 = 0.4x =>r=5
So C.I. of Rs 1600 @ 5% in 3 years=1600(1+ 5/100)^3 -1600 = 1600[ (21/20)^3 - 1] = 252.2 Rs.
Option 4)

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satish kumar   7 years AGO

let p=100 then Amt=140 then S.I=40
S.I=p*r*t/100
40=100*r*8/100
R=5%
c.i=p[(1+r/100)^3-1]
=1600[(1+5/100)^3-1]
252.2

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Mukund Manohar   7 years AGO

Let P = Rs 100
SI = Rs 40
Rate = (SI *100)/(P*T) = 4000/800 = 5%p.a.
Amount after 3 years = 100{1+ (5/100)}^3
= Rs 1852.2
CI = 1852.2 - 1600 = Rs 252.2

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pravallika   7 years AGO

p=100
simple interest= rs.40
rate of interest= 100*40)/(100*8)=5%
now lets fine compound interest of 1600 for 3 years at 5%=1600(1+5/100)^3
ans:252.2

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mohammed fayis   7 years AGO

RI - 5%
1st yr- 80
2nd yr 84
3rd yr 88.2
80+84+88.2

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sujit   7 years AGO

SIMPLE INTEREST=
SUPPOSE I HAVE 100 RS,
then i will get 140 after 8 years..i.e.40 rs more than principle i.e 5% increase in per year,so rate is=5%,

now calculate C.I. for 3 years at the rate of 5%

CI for 1st year=1600*5/100=80;
similaraly for 3 year=252.2 rs

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ABHISHEK KUMAR   7 years AGO

Because rate of that amount is 5℅ so after calculation is simple like compound interest formula.

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Aakash kesarwani   7 years AGO

let the principal amt be x
so simple interest = 0.4*x
0.4*x=(x*R*8)/100
solving above equation we get,
R= 5%

C.I= p[(1+R/100)^n-1]
C.I=1600[(1+5/100)^3 -1]

solving above we get
C.I=252.2 Answer

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Siva   7 years AGO

I= [P(1+(r/n))^nt]-P
= [1600(1+(5/100)^3]-1600
=252.2

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sanju   7 years AGO

Let P=100
SI=40
R=100*SI/(PT)
R=5%
Amount=P(1+5/100)^3
Amount-P=252.2

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SATHEESH V   7 years AGO

40P/100=PTR/100
TR=40
R=40/8=5%

Compound interest=P(1+R/100)^3-P
C.I=1600(1+5/100)^3-1600
=1600(21/20)^3-1600
=1852.2-1600
C.I=252.2

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DIVYANSHU SHEKHAR   7 years AGO

let P=100 SI=Rs40 and T=8 yrs
rate=(100*40)/(100*8)=5%p.a
C.I=1600{(1+5/100)^3-1}=Rs 252.2

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Ajay Sharma   7 years AGO

since amount increased after 8 years is 40%
let 100 be priciple and time = 8
then amount=140=(100*r*8)/100
so,rate is 5%
by compound interest p=1600
r=5
t=3
so,amount = 252.2

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Basant Bothra   7 years AGO

Let,P =100
So, R=40*100/100*8
R=5%.
Now, C.I=1600(1+5/100)^3
C.I=1852.2
Total interest=(1852.2-1600)=252.2

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Chinmay Swarup Chiranjeevi   7 years AGO

through simple interest formula rate is 5% p.a .then using compound interest formula we get the answer.

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Mukesh Kapoor   7 years AGO

Increase of 40% in 8 years will be on 5% of simple interest.
compound interest formula
A= P(1+r/n)^n*t
A= 1600(1+0.05/1)^3
= 1852.2
Compound interest = 1852.2-1600=252.2

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sruthi pujari   7 years AGO

rate of interest =5% since 40x=x*8*r
1600 after years of compound interst
1st year= 5% of 1600=80
2nd year=5% of (1600+80)=80+4=84
3rd year=5% of (1600+80+80+4)=80+4+4+0.2=88.2
total=252.2

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FFETS   7 years AGO

Simple rate of interest is 5%

From that, we can calculate Total amount with 5% compound interest after three years and thereby the interest by subtraction initial amount from total accumulated amount.

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RAJ   7 years AGO

140=100+8R
R=5%
1600(1+5/100)^3-1600=252.2

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TANIYA ROY   7 years AGO

Let the amount for si be x thn amount will be x+.40x=7x/5
7x/5=x+(x*r*8/100)=>r=5%
amount for ci=1600(1+5/100)^3=1852.2
the answer is 1852.5-1600=252.5

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amit kumar   7 years AGO

Let p =principal
principal (after 8 years)=1.4p
intrest (after 8 years)=0.4p
intrest (after 1 year)=0.4p/8=0.05p
so, rate per year (r) =5%
let CI be compound intrest
Amount after 3 years (A)= 1600*(1+0.05)^3=1852.208
so, CI=A-1600= RS 252.208

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gubba ranjith kumar   7 years AGO

S.I: P*T*R/100: X*8*R/100=40X/100
=>R=5
C.I=1600*5(1+105/100+(105/100)(105/100))/100
=252.2

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Shravya   7 years AGO

If the amount is 100 then interest becomes 5 and calculate CI for 1600 at 5% interest for 3 years ..it is 252.2

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DHANANJAY KUMAR   7 years AGO

Let 100 be the amount then interest is 40 % increase
r=(40*100)/(100*8)=5
compound interest = 1600(1+5/100)^3 -1600=252.2
so option 4 is answer

Like? Yes | No (1)