Question

Match the following equation to the correct situation.

Answer 1

Answer:

A.  Last month's electricity bill was 5.4 kW-h less than 30% of this month's bill.

Step-by-step explanation:

The given expression is:

$30\%(b-18)=30\%b-5.4$

The above expression tells us that 30% is of the quantity 'b' and 5.4 is being subtracted from the result of the percentage.

Choice A:

If we consider the present month's bill as 'b'. Then 30% of present month's bill can be represented as 30% of b = 30%b.

Now, if the previous month's bill is 5.4 kW-h less than 30% of this month's bill, then this statement can be represented as:

Previous bill = 30% of Current bill - 5.4 = $30\%b-5.4$

Hence, choice A justifies the given expression.

Choice B:

The expression for choice B could be number of songs available for download from 30% of  'b' artists is $30%b$.

Choice C:

5.4 speeches doesn't make any sense.

Choice D:

5.4 less than 'b' bowls mean $b-5.4$. Now, 30% of this is $30%(b-5.4)=30%b-30%(5.4)$.

This is also not the correct expression.

Therefore, only choice A is the correct justification of the given expression.