Question

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

Answer 1

Answer:

Let the Rs.50 notes by x and Rs.100 notes be y.

∴ Total notes =(x+y) notes

Total notes (given) =25 notes

∴(x+y)=25⟶(i)

Total money Meena has=50x+100y

Total money (given) =Rs.2000

On simplification,

x+2y=40⟶(ii)

On substraction (i) and (ii),

−y=−15

y=15 notes

putting y in (i)

x+y=25

x=10 notes

∴ Rs.50 notes=10 notes.

Rs.100 notes=15 notes.

Answer 2

$\huge \sf Answer :$

Rs 50 notes = 10 and Rs 100 notes = 15

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$\huge \sf Solution :$

Let total Rs 50 notes = x

and total Rs 100 notes = y

∴ Total notes = x + y

But we are given total notes = 25

$\sf \implies x+y = 25 \: \: - ①$

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

$\boxed{\sf y = 15}$ ⠀

Now, by putting y in ①,

x+y=25

x + 15 = 25

x = 25 - 15

$\boxed{\sf x=10}$

∴ Rs 50 notes, x = 10

and Rs 100 notes, y = 15