Question

1) Rekhadidi deposited Rs 10,000 of her savings in two separate banks at the same time. The rate of simple interest per annum is of 6% in one bank and that of 7% in other bank, after 2yrs, if she gets 1280 in total as interest, then let us wrte by calculating, the money she bad deposited separately in each of two banks ?​

Answer 1

Answer:

Given :-

• Rekhadidi deposited Rs 10000 of her savings in two separate banks at the same time. The rate of simple interest per annum of 6% in one bank and that of 7% in other bank after 2 years. She gets Rs 1280 in total as interest.

To Find :-

• What is the money she had deposited separately in each of two banks.

Formula Used :-

$\boxed{\bold{\large{S.I\: =\: \dfrac{P \times r \times t}{100}}}}$

where,

• S.I = Simple Interest
• P = Principal
• r = Rate of Interest
• t = Time

Solution :-

Let, Rekhadidi deposited in 1st bank is Rs x

And, she deposited in 2nd bank is Rs (10000 - x)

Now,

$\small{\red{\bold{\underline{●\: In\: case\: of\: 1st\: bank :-}}}}$

Given :

• Principal (P) = Rs x
• Rate of Interest (r%) = 6%
• Time (t) = 2 years

By substituting the formula we get,

⇒ S.I = $\sf\dfrac{x \times 6 \times 2}{100}$

➠ S.I = $\sf\dfrac{12x}{100}$

Again

$\small{\red{\bold{\underline{●\: In\: case\: of\: 2nd\: bank :-}}}}$

Given :

• Principal (P) = Rs (10000 - x)
• Rate of Interest (r%) = 7%
• Time (t) = 2 years

By substituting the formula we get,

↦ S.I = $\sf\dfrac{(10000 - x) \times 7 \times 2}{100}$

↦ S.I = $\sf\dfrac{(70000 - x) \times 2}{100}$

➦ S.I = $\sf\dfrac{140000 - 14x}{100}$

Now, according to the question,

↪ $\sf\dfrac{12x}{100} +\: \dfrac{140000 - 14x}{100} =\: 1280$

↪ $\sf\dfrac{12x + 140000 - 14x}{100} = 1280$

↪ $\sf\dfrac{- 2x + 140000}{100} = 1280$

By doing cross multiplication we get,

↪ $\sf{- 2x + 140000 = 128000}$

↪ $\sf{- 2x = 128000 - 140000}$

↪ $\sf{- 2x = - 12000}$

↪ x = $\sf\dfrac{\cancel{- 12000}}{\cancel{- 2}}$

➪ x = Rs 6000

Hence, the required money she deposited separately in each of two banks are,

✧ In 1st bank = Rs x = Rs 6000

✧ In second bank = Rs (10000 - x) = Rs (10000 - 6000) = Rs 4000

$\therefore$ Rekhadidi deposited Rs 6000 in 1st bank and Rs 4000 in 2nd bank.

Answer 2

1) Rekhadidi deposited Rs 10,000 of her savings in two separate banks at the same time. The rate of simple interest per annum is of 6% in one bank and that of 7% in other bank, after 2yrs, if she gets 1280 in total as interest, then let us wrte by calculating, the money she bad deposited separately in each of two banks