Percents

Problem:

An acquisitions officer has negotiated a contract with a supplier for deliveries that are 12 per cent less than the retail price. If the delivery would have cost $6000 retail, how much did the officer save?

$6000 × .12 = $720 saved

Definition:

A per cent is a ratio of two similar quantities expressed in hundreths. Per cents are usually written with the % symbol instead of the decimal fraction or decimal number, but all three ways of expression are equivalent.

Example: 6% = .06 = 6/100

Example: 25% = .25 = 25/100=1/4

Example: 175% = 1.75 = 175/100=1 3/4

Example: 1/10% = .001 = .1/100=1/1000

Notes about per cents:

To express a per cent as a decimal, omit the % sign and move the decimal point two places to the left.

To express a per cent as a fraction, omit the % sign, write the per cent as the numerator with the denominator 100 and reduce the fraction.

When you compute a percentage, you are selecting the number of hundreths represented by the per cent from a number called the base.

percentage = per cent × base

The per cent is a ratio and, therefore, an abstract number.

The percentage is an amount which has the same type of unit as the base.

---

Try a few problems using per cent:

1.Express as a decimal and as a fraction: 6 1/4 %

2.Express as a per cent:1.25

3.Express as a per cent:3/5

4.The average transportation cost for moving a troop from point A to point B increased from $350,000 to $500,000. Find the per cent of increase in the cost.

5.After a cut of 5%, a department has a budget of $585,000. What was the budget before the cut?