Answer: To calculate how much Mr. Owusu paid for using 720 units in a month, we need to consider the different tiers of electricity charges and apply the corresponding rates to each tier.
Given:
First 50 units: $4000
Next 100 units: $120 per unit
Next 150 units: $150 per unit
Next 300 units: $220 per unit
Remaining units: $350 per unit
Step 1: Calculate the cost for the first 50 units:
Cost for first 50 units = 50 * $4000 = $200000
Step 2: Calculate the cost for the next 100 units (units 51 to 150):
Cost for next 100 units = 100 * $120 = $12000
Step 3: Calculate the cost for the next 150 units (units 151 to 300):
Cost for next 150 units = 150 * $150 = $22500
Step 4: Calculate the cost for the next 300 units (units 301 to 600):
Cost for next 300 units = 300 * $220 = $66000
Step 5: Calculate the cost for the remaining units (units 601 to 720):
Cost for remaining units = 120 * $350 = $42000
Now, add up all the costs to get the total amount Mr. Owusu paid for using 720 units:
Total cost = $200000 + $12000 + $22500 + $66000 + $42000 = $342500
So, Mr. Owusu paid $342500 for using 720 units in a month.
Now, to find the number of units of electricity consumed by the man who paid $73260, we need to reverse the calculation process.
Given: Total cost = $73260
Step 1: Determine the tier in which the total cost falls.
The first 50 units cost $4000. This covers a total cost of $4000.
Next 100 units cost $120 per unit. This covers a total cost of $12000.
Next 150 units cost $150 per unit. This covers a total cost of $22500.
Next 300 units cost $220 per unit. This covers a total cost of $66000.
So far, the total cost covered is $4000 + $12000 + $22500 + $66000 = $104500.
Step 2: Calculate the remaining cost:
Remaining cost = Total cost - Total cost covered
Remaining cost = $73260 - $104500 = -$31240
Since the remaining cost is negative, it means the man consumed electricity beyond the first 600 units. Now, we need to calculate the number of units for the remaining cost using the rate of $350 per unit.
Step 3: Calculate the number of units for the remaining cost:
Number of units for remaining cost = Remaining cost / $350 per unit
Number of units for remaining cost = -$31240 / $350 ≈ -89.257
Since the number of units cannot be negative, we take the absolute value:
Number of units for remaining cost ≈ |-89.257| ≈ 89.257
So, the man consumed approximately 89.257 units of electricity in a month.