Question

According to the rate of electricity charge, the cost up to 20 units is Rs 3 per unit & Rs 7 per unit for 21 units to 30 units. How many units can be consumed for Rs 173 if the Service Charge is Rs 50?​

Answer 1

Subtract the service charge from the total amount:

Rs 173 - Rs 50 = Rs 123.

Now, we have Rs 123 to spend on electricity.

Up to 20 units cost Rs 3 per unit, so for the first 20 units, it would be

20 units * Rs 3 = Rs 60.

Subtract this from the remaining amount:

Rs 123 - Rs 60 = Rs 63.

The cost for each unit beyond 20 is Rs 7. Divide the remaining amount by the cost per unit: Rs 63 / Rs 7 = 9 units.

Therefore, you can consume 20 + 9 = 29 units for Rs 173 with a service charge of Rs 50.