Question

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

Answer 1

let the cost of book and pens is x andy
6x+7y=79
7x+5y=77
now solve these you got the value of x andy
put the value of x and yin
x+2y you got an answer

Answer 2

6b+7p=79.........................(1)
7b+5p=77.........................(2)

subtracting 2p-b=2
b=2p-2
solving for p in (2).... p=91/19=7

asper the question...1b+2p=4p-2=26

ANswer=26