Question

The total cost of 6books and 7pens is 79rupees and total cost of 7books and 5pens is 77rupees.Find the cost of 1 book and 2 pens

Answer 1

let the cost of 1 book be x

let the cost of 1 pen be y

acc. to ques.

6x + 7y = 79

6x= 79- 7y
x =(79- 7y)/6


7x + 5y =77
(553- 49y)/6 +5y =77
553 -49y +30y = 462
-19y = -91
y= rs. 4.7

x= (79 -33.5)/6
x=45.5/6
 =7.5