Question

ACCORDING to the rate of electricity charge, the minimum charge up to 20 unit is Rs 80 and the cost per unit from 21 units to 250 units is Rs 7.30. How many units were consumed by Rs 1248?

​

Answer 1

180

Explanation:

let x = total units of electricity after 250 units

the total units of electricity consumed can be determined using the formula below

80 + 7.3x = 1248

7.3x = 1248 - 80

7.3x = 1168

divide both sides of the equation by 7.3

x = 1168 / 7.3

x = 160

total electricity consumed = 160 + 20 = 180

160