Question

52. In what time 8000 amounts to 12000 at the rate of 4% per annum?​

Answer 1

Answer:

It is given that P=Rs.6,000

A=Rs.8,000

We know that S.I=A−P

Substituting the values =8000−6000=Rs.2000

Also, duration is given as T=4 years

Here,

Rate (R) = (S.I×100)/(P×T)

Substituting the values =(2000×100)/(6000×4)

=25/3%=8(1/3)% p.a

Now, we need to find the time that will result to an amount of Rs.700 at same rate.

So,

P=Rs.525

A=Rs.700

S.I=A−P

=700−525=Rs.175

Also, Rate (R)=25/3% p.a

So,

Time (T)= (S.I×100)/(P×R)

Substituting the values =(175×100×3)/(525×25)

=4

So we get =4 years

Answer 2

In 12.5 years  8000 amounts to 12000 at the rate of 4% per annum

Given:

• P = 8000           ( P + principal)
• A = 12000         (A = Amount)
• R = 4 % per annum  ( R = Rate of Interest)

To Find:

• Time period

Solution:

• SI = P × R × T /100        ( SI = Simple Interest)
• SI = A - P

Step 1:

Calculate Simple  interest (SI)

SI = A - P

SI = 12000 - 8000

SI = 4000

Step 2:

Use formula  for simple interest and substitute the values

SI = P × R × T /100

4000 = 8000   × 4 × T /100

Step 3:

Solve for T:

4000 = 80   × 4 × T  

=> 1000 = 80 × T

=> 100 = 8T

=> T = 100/8

=> T = 12.5

In 12.5 years  8000 amounts to 12000 at the rate of 4% per annum