If ₹64 amount to ₹83.20 in 2years, what will ₹86 amount to in 4 yrs at same rate?
Answers
Answer:
137.6
Step-by-step explanation:
P
1
=Rs.64
A 3
1
=83
T
1
=2
Let Rate be R.
A=P(1+
100
RT
)
⇒83.2=64(1+
100
2R
)
⇒
64
83.2
=1+
100
2R
∴ Rate =15%
Now,
P
2
=86
T
=2
=86
R=15%
A=P(1+
100
RT
)
⇒A=86(1+
100
15×4
)=137.6
Solution!!
The concept of simple interest has to be used here.
Principal = Rs 64
Amount = Rs 83.20
Time = 2 years
Rate of interest = x
Amount = Principal + SI
Rs 83.20 = Rs 64 + SI
SI = Rs 83.20 - Rs 64
SI = Rs 19.2
SI = (P × R × T)/100
19.2 = (64 × x × 2)/100
1920 = 64 × 2 × x
1920 = 128 × x
x = 1920 ÷ 128
x = 15
Rate of interest= 15%
In the second case:-
Principal = Rs 86
Rate of interest = 15%
Time = 4 years
SI = (P × R × T)/100
SI = (86 × 15 × 4)/100
SI = 5160/100
SI = Rs 51.6
Amount = Principal + SI
Amount = Rs 86 + Rs 51.6
Amount = Rs 137.6
Abbreviations used:-
P → Principal
R → Rate of interest
T → Time
SI → Simple interest