Question

A sum at simple interest of 4% per annum amounts to ₹3120 in 5years.Find the sum
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Answer 1

Step-by-step explanation:

Let Rs. P be the sum

At 12% per annum the interest for 8 years

=100P×12×8=2524P

qat 14% per annum the interest for 5 years

=100P×14×5=107P

ACQ,

⇒2524P=3120+107P

⇒(2524−107)P=3120

⇒(10096−70)P=3120

⇒(10026)P=3120

⇒P=263120×100

⇒P=12000

Answer 2

Answer:

The sum is Rs.15,600

Explanation:

We know,

$\rm \longrightarrow \: Simple \: interest = \dfrac{p \times r \times t}{100}$

Where,

• p denotes the principal or the sum.
• simple interest = Rs. 3120
• r(rate) = 4%
• t(time) = 5 years.

Substituting the given values,

$\rm \implies \: 3120 = \dfrac{p \times 4 \times 5}{100}$

$\rm \implies \: 3120 = \dfrac{20p}{100}$

$\rm \implies \: 3120 = \dfrac{p}{5}$

$\rm \implies \: 3120 \ast 5 = p$

$\rm \implies \: 15600 = p$

∴ The sum is Rs. 15,600