Deducting a 20% discount is the same as charging 80% of the price, so $240.00 is 80% of the original price, which we call \(\displaystyle P\). Just solve this equation:

\(\displaystyle P \cdot 0.80 = 240.00\)

\(\displaystyle P = 240 \div 0.80 = 300.00\)

The suit originally cost $300.00

Put the percent over 100 and simplify as follows:

\(\displaystyle \frac{7 \tfrac{1}{2} }{100} = 7 \tfrac{1}{2} \div 100 = \frac{15}{2} \cdot \frac{1}{100} =\frac{3}{2} \cdot \frac{1}{20} = \frac{3}{40}\)

Note: all of these choices are equivalent to \(\displaystyle 7 \tfrac{1}{2}\) %; but only \(\displaystyle \frac{3}{40}\) is in lowest terms.

The coat is $10 cheaper than normal. 

\(\displaystyle \frac{10}{40}=0.25=25\%\)

The word approximately tells you that you need to estimate to get the answer. $652.20 can round up to $700 because 52.20 is more than half of 100. Since 10% is equal to the decimal 0.10, we multiply 700 by this number in order to find out what 10% of 700 is.

\(\displaystyle 700\times 0.10 = 70\)

The answer is  \(\displaystyle \$70\)

Multiply the price of the groceries before tax - $154.92 - by the decimal equivalent of 9% , which is 0.09. Round this tax to the nearest hundredth (cents), then add to the price of the groceries.

Tax: \(\displaystyle \$154.92 \cdot 0.09 \approx \$13.94\)

Price after tax: \(\displaystyle \$154.92 + \$13.94 =\$168.86\)

The storewide sale discounts the shirt by 50%:

\(\displaystyle .5\times \$42=\$21\)

Susan also has the 10% off coupon, so she's really paying 90% of the cost of the shirt:

\(\displaystyle .9\times \$21=\$18.90\)

The total number of plants has to be divisible by 3.  Of the answer choices, the only one that is divisible by 3 is 18.  You can check this because numbers that are divisible have the sum of their digits also divisible by 3. For example,

\(\displaystyle 1 + 8 = 9\) 

which is divisible by 3, so 18 is divisible by 3.

3% of 5,319 can be calculated by multiplying 5,319 by 0.03, the decimal equivalent of 3%:

\(\displaystyle 5,319 \times 0.03 = ?\)

Multiply 5,319 by 3, then move the decimal point so that two digits are to the right:

\(\displaystyle 5,319 \times 3 =15,957\),

so

\(\displaystyle 5,319 \times 0.03 = 159.57\)

Rounded to the nearest whole number, this is 160 signatures.

First, multiply the original price by the sale percentage:

\(\displaystyle 345 *.40=138\)

Then, subtract that amount from the original price to get the sale price:

\(\displaystyle 345-138=207\).

The laptop's current sale price is \(\displaystyle \$ 207.00\)

First, multiply 45 by 0.37:

\(\displaystyle 45 * .37=16.65\)

Then, subtract that amount from 45.00 to find the sale price:

\(\displaystyle 45-16.65=28.35\)

Answer: The dress' sale price is $28.35.