Question

Raju buys 7 books and 6 pens for Rs 2750 and anand buys 3 books and 5 pens of same kind for Rs 1300 what are the respective cost of books and pens

Answer 1

Answer:

Rs. 350 and Rs. 50

Step-by-step explanation:

• Cost of a book- x
• Cost of a pen- y

As per given:

1. 7x+6y=2750

2. 3x+5y=1300

If we multiply the second equation to 7 and the first one by 3, in order to substitute one of unknowns:

3(7x+6y)=3*2750 => 21x+18y=8250

7(3x+5y)=7*1300 => 21x+35y=9100

35y-18y=9100-8250

17y=850

y=50

Find x using one of equations:

x=350

So, book costs Rs. 350 and pen costs Rs. 50