Q1 of 25 Page 90

In an envelope there are some 5 rupee notes and some 10 rupee notes. Total amount of these notes together is 350 rupees. Number of 5 rupee notes are less by 10 than number of 10 rupee notes. Then find the number of 5 rupee and 10 rupee notes.

Let the number of 5 rupees notes = x


Let the number of 10 rupees notes = y


Given, Total amount is 350 Rupees


⇒ 5x + 10y = 350 eq.[1]


Also,


Number of 5 rupees notes are less by 10 than number of 10 rupees note,


⇒ x = y - 10 eq.[2]


Putting [2] in [1]


⇒ 5(y - 10) + 10y = 350


⇒ 5y - 50 + 10y = 350


⇒ 15y = 400


⇒ y = 30


Then, x = y – 10


⇒ x = 30 – 10


⇒ x = 20.


Answer: 30 notes of Rs 5 and 20 notes of Rs. 10.


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