Lesson · M.1.1
Fractions, decimals, and percentages
How to convert confidently between fractions, decimals, and percentages, the three forms the TEAS switches between without warning, using only the four-function calculator on screen.
By the end of this lesson you can
- Convert any value between a fraction, a decimal, and a percentage in either direction.
- Carry out a fraction to decimal conversion as a long division, including when the decimal does not terminate.
- Simplify a decimal or a decimal percentage to a fraction in lowest terms.
- Read decimal place value accurately enough to round and to compare two close values.
- A fraction, a decimal, and a percentage can all describe the same quantity. Learn to move between them rather than treating them as three separate topics.
- Fraction to decimal: divide the numerator by the denominator. Decimal to percentage: multiply by 100.
- Percentage to decimal: divide by 100. Decimal to fraction: put the digits over the matching power of ten, then simplify.
- A division that never reaches a remainder of zero is carried to the thousandths place and rounded back to the hundredths.
- Read place value from the last nonzero digit, since a misread place changes the value by a factor of ten.
Check yourself
0 / 51In the fraction 3/8, what does the denominator tell you?
2According to the lesson, how do you convert a fraction into a decimal?
3What is the correct way to change a decimal into a percentage, based on the lesson?
4A question gives you 45% and asks for the decimal form. What should you do?
5Following the method in the lesson, what fraction (before simplifying) matches the decimal 0.125?