Explanation:
Let's assume the basic fee for water is $X per unit and the tariff for consumption is 5% increase per unit. VAT (Value Added Tax) is calculated at a rate of Y% on the total cost, including the basic fee and the tariff.
Given that the consumption is 15 units, the total cost for the consumption of 15 units of water without VAT can be calculated as:
Total cost without VAT = Basic fee + (Tariff rate * Number of units)
Tariff rate = 5% increase per unit, so it would be 1 + 5% = 1.05
Total cost without VAT = X + (1.05 * 15) = X + 15.75
Now, let's assume the VAT rate is Z%. The total cost including VAT can be calculated as:
Total cost including VAT = Total cost without VAT + (VAT rate * Total cost without VAT)
Total cost including VAT = (X + 15.75) + (Z% * (X + 15.75))
To calculate the amount by which the total cost, including VAT, for the consumption of 15 units of water will increase, we need to subtract the initial cost from the increased cost:
Increased cost = Total cost including VAT - Total cost without VAT
Increased cost = [(X + 15.75) + (Z% * (X + 15.75))] - (X + 15.75)
Simplifying, we get:
Increased cost = Z% * (X + 15.75)
So, the amount by which the total cost, including VAT, for the consumption of 15 units of water will increase depends on the value of Z% (the VAT rate) and X (the initial basic fee for water). Once we have these values, we can calculate the increased cost accordingly.