Basic Math Skills Review. Percents. Percent. Percent (from per centum ) means per hundred or divide by one hundred. The “%” sign is used to show the number of parts per one hundred parts.
Changing a fraction to a decimal
Divide the numerator by the denominator.
Changing a decimal to a fraction
Drop decimal and divide by the highest place value.
Simplify, if possible.
Changing decimal to percent
Multiply by 100 and attach percent sign. It’s the same as moving the decimal 2 places to the right. 0.375 = 37.5%
Changing from percent to decimal
Divide by 100. It’s the same as moving the decimal 2 places to the left. 38% = 0.38
Changing percent to fraction
Drop % sign and divide by 100. Simplify if possible.
Changing from a fraction to a percent
Multiply by 100 and attach a % symbol.
Percentage = Percent x Whole Quantity
To find a percentage or part of a whole quantity:
A patient reports that he drank 75% of his eight ounce cup of coffee. How much coffee did he drink?
1) Change 75% to a decimal: 75% → 0.75
2) Multiply 0.75 x 8 ounces to get 6 ounces.
1) What is 20% of 75? X = 0.20 x 75
2) Ten is what percent of 15? 10 = p x 15
3) Table salt (NaCl) is 40% sodium by weight. If a box of salt weighs 18 ounces, how much sodium is in the box of salt?
4) A student’s tuition bill is $17,651. Her financial aid pays 80%. How much will the student owe?
5) If 1 roll of tape costs $0.69, how much do 3½ rolls costs? (Round to the nearest cent)
6) If 1 centimeter equals ⅜ inch, how many centimeters is a nail that measures 3 inches?
7) You work in a health care clinic where each employee must work 25% of 8 major holidays. How many holidays will you expect to work?