Cost of 4 pens, 6 note books and 9 files is Rs 305. Cost of 3 pens, 4 notebooks and 2 files is Rs 145. What is the cost (in Rs) of 5 pens, 8 notebooks and 16 files?
Answers
Cost o f4 pens, 6 note books and 9 files is Rs 305
⇒ 4P + 6N + 9F = 305
Cost of 3 pens, 4 notebooks and 2 files is Rs 145
⇒ 3P + 4N + 2F = 145
Putting the two equations together:
4P + 6N + 9F = 305 ------------------- [ 1 ]
3P + 4N + 2F = 145 ------------------- [ 2 ]
Multiply equation [ 1 ] by 2:
8P + 12N + 18F = 610 ------------------- [ 3 ]
Subtract equation [ 2 ] from equation [ 3 ] :
5P + 8N + 16F = 465
Answer: 5 Pens, 8 notebooks and 16 files cost Rs 465
Equation2 :
4P + 6N + 9F = 305
multiply by 2:
4x2P + 6x2N + 9x2F = 305x2
So I got:
8P + 12N + 18F = 610
Cost of 4 pens, 6 note books and 9 files is Rs 305⇒ 4P + 6N + 9F = 305Cost of 3 pens, 4 notebooks and 2 files is Rs 145 and it is ⇒ 3P + 4N + 2F = 145.
Putting the two equations 4P + 6N + 9F = 305 3P + 4N + 2F = 145 by Subtract equation equation: 5P + 8N + 16F = 465Answer: 5 Pens, 8 notebooks and 16 files cost Rs 465.