Question

a house holder used to spend rs 120 per month when the price of wheat rose from 10 paise per kg for the same amount he could purchase 5 kg less .if rs x per kg was the real price 10x^2 -x-24=0
solve this equation and find the new price of wheat​

Answer 1

Answer:

Step-by-step explanation:

10x^2 -x-24=0

10x^2 -16x + 15x -24=0

2x(5x-8)+3(5x-8) = 0

(2x+3)(5x-8) =0

x= -3/2 and 8/5

Initial cost of x kg of wheat = 120

Initial cost of 1 kg of wheat = 120/x

New cost of 1 kg wheat = 0.1 + old cost = 0.1 + 120/x

This means that by spending the same amount of money (120 rupees) now she bought  5 kg less amount of wheat.

(0.1 + 120/x) (x -5) = 120

(0.1x+120)(x-5) =120x

0.1x²+120x-0.5x+600=0

0.1x²-0.5x+600=0

x²-5x+6000=0

x²-80x+75x-6000=0

x(x-80)+75(x+80)=0

(x+75)(x-80) =0

x=80 or -75

So x=80