Question

The cost of petrol rises by 2 Naira per litre. Last week a motorist bought 25 litre At the old price. This week she bought 20 litre at the new price. All together, the petrol cost 3640 Naira. What was the old price for 1 litre

Answer 1

Answer:

25 * x + 20 * (x+2) = 3640

simplify to get 25 * x + 20 * x + 40 = 3640

combine like terms to get 45 * x + 40 = 3640

subtract 40 from both sides of the equation to get 45 * x = 3600

divide both sides of the equation by 45 to get x = 80.

the old price per liter is 80.

the new price per liter is 82.

25 * 80 + 20 * 82 = 3640.

old price per liter is 80 naira.