The cost of 5 books and 7 pens together is Rs 79 where as the cost of 7 books and 5 pens together is Rs 77 . Find the cost of 1 book and 2 pencils.
Answers
Answered by
0
ATQ
5x+7y = ₹79
7x+5y = ₹77
-------------------
12x+12y = ₹156
12(x+y) = ₹156
x+y = ₹156/12
x+y = ₹13
x = ₹13-y
Putting the above value of x in any of the above two equations.
5(13-y)+7y = ₹79
65-5y+7y = ₹79
2y = ₹14
y = ₹7
x = ₹13-₹7 = ₹6
Cost of 1 book = ₹6
Cost of 2 pens = 2y = ₹2*7 = ₹14
Similar questions