Question

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.​

Answer 1

Question:

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.

Given:

1. In an envelope there are some 5 rupee notes and some 10 rupee notes.
2. Total amount of these notes together = 350 rupees.
3. Number of 5 rupee notes are less by 10 than number of 10 rupee notes.

To Find:

• Number of 5 rupee & 10 rupee notes.

Solution:

Let x be the number of notes of Rs. 5 & y be the number of notes of Rs. 10.

According to this question,

→ 5x + 10y = 350

→ x + 2y = 70 –––––(1)

Also,

→ x = y - 10

→ x - y = -10–––––(2)

Subtract equation (2) from (1)

→ (x - y) - (x + 2y) = 70 -10

→ 0 - 3y = 60

→ 3y = 60

→ y = 20

Put it in (1) we get,

x + 2y = 70

→ x + 2(20) = 70

→ x + 40 = 70

→ x = 70 - 40

→ x = 30

Hence,

The number of Rs. 5 notes are 30 & the number of Rs. 10 notes are 20.