Question

Meena went to a bank to withdraw Rs. 2000. She asked the cashier to give Rs. 50 and Rs. 100 notes only. Meena got 25 notes in all. Find how many notes of Rs. 50 and Rs. 100 she received?​

Answer 1

Answer :

Total Rs. 50 notes = 10

Total Rs. 100 notes = 15

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Solution :

Let total Rs 50 notes = x

and total Rs 100 notes = y

∴ Total notes = x+y

But we are given total notes = 25

$\sf : \implies x+y = 25 \: \: - ①$

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Now, Meena has total money = 50x + 100y

But we are given total money = Rs. 2000

$\sf : \implies 50x+100y=2000$

$\sf : \implies 50(x+2y)=2000$

$\sf : \implies x+2y = \dfrac{2000}{50}$

$\sf : \implies x+2y = \dfrac{\cancel{2000}^{40}}{\cancel{50}}$

$\sf : \implies x+2y = 40 \: \: - ②$

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On substraction of ① and ②,

(x+y) - (x+2y) = 25 - 40

x + y - x - 2y = - 15

- y = - 15

$\underline{\boxed{\sf y = 15}}$

Now, by putting y in ①,

x+y=25

x + 15 = 25

x = 25 - 15

$\underline{\boxed{\sf x=10}}$

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∴ Rs 50 notes, x = 10

and Rs 100 notes, y = 15

Answer 2

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