Question

the simple interest of Rs 24000in 3years 4% per annum will be same as simple interest on Rs7200at 5% per annum in how many years​

Answer 1

Answer:

8 years are required.

Step-by-step explanation:

Given :

Principal = Rs.24000 and Rs.7200

Time = 3 years

Rate = 4% and 5%

To find :

The time

Solution :

Case I -

• P₁ = 24000
• T₁ = 3
• R₁ = 4%

⇒ SI = PRT/100

⇒ SI = (24000 × 4 × 3)/100

⇒ SI = 240 ×  12

⇒ SI = 2880

_________________________________________________

Case II -

• SI = 2880
• P₂ = 7200
• R₂ = 5%
• T₂ = ??

⇒ SI = PRT/100

⇒ 2880 = (7200 × 5 × T₂)/100

⇒ 2880 = 360 × T₂

⇒T₂ = 2880/360

⇒ T₂ = 8

Time needed = 8 years

∴ 8 years are required.

Answer 2

${\boxed{\mathtt{\green{Given}}}}$

Condition 1st

⇢ Principal = Rs 24,000

⇢Time = 3 years

⇢ Rate = 4%

$\boxed{Formula \: = \: \frac{ \:P.R .T}{100} }$

$Simple \: interest = \frac{24000 \times 3 \times 4}{100}$

⇢ 240 × 3 × 4

⇢ 240 × 12

⇢ 2880

${ \boxed{ \mathtt {\red{ = \: 2880}}}}$

Condition 2nd

⇢ Principal = Rs 7200

⇢ Rate = 5 %

⇢ Simple interest = Rs 2880

⭐ Formula is mentioned above .

$2880 \: = \frac{7200 \times 5 \times \: time}{100}$

$2880 \times 100 = 36000 \times time$

$\frac{288}{36} = time$

${\boxed{ \mathtt {\red{time \: = 8 \: years}}}}$

So , The simple interest on Rs 72,00 at the rate of 5% for 8 years will be Rs 2880