Ann went to a shop to buy 2 pens and 5 pencils. If the cost of 2 pens was 30 rupees and total amount of her purchase was 80 rupees. How much did each pen and pencil cost?

Solution:

Let x be the cost of a pen.

Let y be the cost of a pencil.

The cost of 2 pens are 30 Rs.

So,the algebraic expression is

2x = 30

x = 30/2 = 15

The cost of a pen = 15 Rs

Ann purchase 2 pens and 5 pencils in total amount 80 Rs.

So, the algebraic expression is

2x+5y = 80

2*15+5y = 80

30+5y = 80

5y = 80-30

5y = 50

y = 50/5 = 10

The cost of a pencil = 10 Rs

Answer:

The cost of a pen = 15 Rs

The cost of a pencil = 10 Rs