Da VIP Academy / GED / Math / Number Sense & Operations
Decimals & Percents
Convert among decimals, fractions, and percents, and compute with decimals.
How it works
Percent means per hundred
35% = 0.35 = 35/100 = 7/20. To turn a percent into a decimal, move the decimal point two places left. To go the other way, move it two places right.
Percent of a number
Multiply: 18% of 250 = 0.18 × 250 = 45. On a calculator that is one keystroke sequence; by hand, 10% is 25 and 8% is 20, so 25 + 20 = 45.
Worked examples
Write 0.35 as a fraction in lowest terms.
- 0.35 = 35/100.
- Divide top and bottom by 5.
- Answer: 7/20.
Words to know
- Percent
- A ratio out of 100.
- Place value
- The value a digit has because of its position.
Test-day tips
- • Find 10% first, then build the rest from it.
- • Keep decimal points lined up when adding money.