Answer:
140 units
Step-by-step explanation:
Our first task is to determine the amount left for electricity consumption after having bought the first 50 units at Rs. 7.30 per unit
Cost of first 50 units:
1unit=Rs. 7.30
50 units=Rs. 7.30*50
50 units=Rs.365
Amount left=total amount-cost of 50 units
total amount for consumption=Rs 1139
Amount left=Rs 1139-Rs.365
Amount left=Rs 774
Units consumable with the balance=Rs 774/Rs. 8.60
Units consumable with the balance=90 units
Units that can be consumed with Rs 1139=50 units+90 units
Units that can be consumed with Rs 1139=140 units