Question

Q5. Find the compound interest on Rs.800
for 2 years if the rates are 20% and 25%
respectively.
O Rs.400
Rs.200
O Rs.80
None​

Answer 1

Answer:

$\pink {CompoundInterest=Rs1082}$

Step-by-step explanation:

$\begin{gathered} i) Principal (P) = Rs \: 4000 ,\\Time (T) = 2 \: years \\Rate \: of \: interest (r) = 10\% \:per \: annum \end{gathered}$

i)Principal(P)=Rs4000,

Time(T)=2years

Rateofinterest(r)=10%perannum

$Conversation \: period (n) = 2Conversationperiod(n)=2$

$\boxed {\pink { Amount (A) = P\left( 1 + \frac{r}{100}\right)^{n} }}$

Amount(A)=P(1+

100

r

)

n

$\begin{gathered} A_{1} = 4000\left( 1 + \frac{10}{100}\right)^{2}\\= 4000 \times (1.1)^{2}\\= 4000\times 1.1 \times 1.1 \\= Rs\:4840 \end{gathered}$

A

1

=4000(1+

100

10

)

2

=4000×(1.1)

2

=4000×1.1×1.1

=Rs4840

$\begin{gathered} Compound \: Interest (C.I) = A_{1} - P\\= Rs\:4840 - Rs\: 4000 \\= Rs\: 840 \: ---(1) \end{gathered}$

CompoundInterest(C.I)=A

1

−P

=Rs4840−Rs4000

=Rs840−−−(1)

$\begin{gathered} ii ) For \: 6 \: months \: we \:have \: to \: find \\simple \: Interest \end{gathered}$

ii)For6monthswehavetofind

simpleInterest

$\begin{gathered} Principal = A_{1} = Rs \: 4840 ,\\R = 10\% \\Time (T) = \frac{1}{2} \: year \end{gathered}$

Principal=A

1

=Rs4840,

R=10%

Time(T)=

2

1

year

$\boxed { \pink { Simple \: Interest (I) = \frac{PTR}{100} }}$

SimpleInterest(I)=

100

PTR

$\begin{gathered} = \frac{ 4840 \times \frac{1}{2} \times 10}{100}\\= \frac{ 4840 \times 5}{100} \\= Rs\: 242 \: ---(2)\end{gathered}$

=

100

4840×

2

1

×10

=

100

4840×5

=Rs242−−−(2)

Therefore,.

$\begin{gathered} Compound \: Interest = (1) + (2) \\= Rs \: 840 + Rs\: 242 \\= Rs\:1082 \end{gathered}$

CompoundInterest=(1)+(2)

=Rs840+Rs242

=Rs1082

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