Question

if 70000 becomes 77000 at 5% simple interest the number of year is​

Answer 1

Answer :-

• The number of years is 2.

To find :-

• The number of years.

Step-by-step explanation :-

• Here, the principal, rate and amount have been given to us. We have to find the time.

Before finding the time, we have to find the simple interest!

We know that :-

$\underline{ \boxed{\sf SI = Amount - Principal}}$

Here,

• Amount = Rs 77000.
• Principal = Rs 70000.

Hence,

$\bf SI =77000 - 70000$

$\bf SI = Rs \: 7000.$

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Now, as we know the simple interest, let's find the time!

We know that :-

$\underline{ \boxed{\sf SI = \dfrac{Principal \times Rate \times Time}{100}}}$

Here,

• Simple interest = Rs 7000.
• Principal = Rs 70000.
• Rate = 5% per annum.

• Let the time be t.

Substituting the given values in this formula,

$\tt7000 = \dfrac{70000 \times 5 \times t}{100}$

Multiplying 70000 with 5,

$\tt7000 = \dfrac{350000 \times t}{100}$

Multiplying 350000 with t,

$\tt7000 = \dfrac{350000t}{100}$

Transposing 100 from RHS to LHS, changing it's sign,

$\tt7000 \times 100 = 350000t$

Multiplying 7000 with 100,

$\tt700000 = 350000t$

Transposing 350000 from RHS to LHS, changing it's sign,

$\tt\dfrac{700000}{350000} = t$

Dividing 700000 by 350000,

$\overline{\boxed{\tt2 \: years = t}}$

• Hence, the time is 2 years.

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Answer 2

Given :

• Amount (A) = Rs 77000
• Principal (P) = Rs 70000
• Rate (R) = 5% simple interest

To Find :

• Time (T)

Solution :

Finding Simple Interest first :

We know that,

★ Amount = Simple Interest + Principal

⟶⠀Amount = Simple Interest + Principal

⟶⠀77000 = Simple Interest + 70000

⟶⠀77000 - 70000 = Simple Interest

⟶⠀Rs 7000 = Simple Interest

Finding Time Period :

We know that,

★ SI = P × R × T/100

where

• SI stands for Simple Interest
• P stands for Principal
• R stands for Rate
• T stands for Time

⟶⠀SI = P × R × Time/100

⟶⠀7000 = 70000 × 5 × Time/100

⟶⠀7000 = 700 × 5 × Time

⟶⠀7000/700 = 5 × Time

⟶⠀70/7 = 5 × Time

⟶⠀10 = 5 × Time

⟶⠀10/5 = Time

⟶⠀2 = Time

So, Time Period is 2 years.

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