Given:
Meena went to a bank to withdraw Rs 2000. She asked the cashier to give her Rs 50 and Rs 100 notes only. Meena got 25 notes in all.
To find:
How many notes of Rs 50 and Rs 100 she received.
Solution:
Let the number of Rs. 50 and Rs. 100 notes be ‘a’ and ‘b’.
Given,
Meena went to a bank to withdraw Rs 2000. She asked the cashier to give her Rs 50 and Rs 100 notes only.
⇒ 50a + 100b = 2000
⇒ a + 2b = 40 ------- (1)
Also
Meena got 25 notes in all.
⇒ a + b = 25 ----- (2)
(1) – (2)
a + 2b - (a + b) = 40 - 25
⇒ a + 2b - a - b = 40 - 25
⇒ b = 15
Put the value of b in eq. 1 to get,
a+15 = 25
⇒ a = 25 - 15
Thus, a = 10
Therefore,
Meena received 10 notes of denomination 50 and 15 notes of denomination 100.
