Decimals, Fractions, Percentages

Decimals, Fractions, Percentages

Understanding Decimals, Fractions, and Percentages

  • Decimals, fractions, and percentages are different ways of expressing proportions and quantities.
  • A fraction expresses a part of a whole and is expressed as a/b where a is the numerator (part) and b is the denominator (whole).
  • A decimal is a number based on the number 10 and is expressed with a decimal point (.).
  • A percentage is a way of expressing a number as a fraction of 100 and is expressed by the % symbol.

Converting Between Decimals, Fractions, and Percentages

  • To convert a decimal to a fraction, consider the place value of the decimal, make it the numerator and make the corresponding multiple of 10 (depending on how many decimal places) the denominator. Simplify if possible.
  • To convert a fraction to a decimal, divide the numerator by the denominator using long or short division.
  • To convert a decimal to a percentage, multiply the decimal by 100 and add the % symbol.
  • To convert a percentage to a decimal, remove the % symbol and divide by 100.
  • To convert a fraction to a percentage, first convert the fraction to a decimal, and then convert the decimal to a percentage.
  • To convert a percentage to a fraction, crate a fraction with the percentage as the numerator and 100 as the denominator, then simplify if possible.

Common Mistakes When Working With Decimals, Fractions, and Percentages

  • A common mistake when dealing with decimals and fractions is misunderstanding the place value of the number. For example, 0.5 is not the same as 0.05.
  • Another frequent error is incorrect conversion between percentages and fractions. For example, 50% is not equivalent to 50/100 but rather to 1/2 or 0.5.
  • Ordering fractions and decimals can often cause problems. Remember to convert all values to the same form to compare and order correctly.

Practical Tips for Mastering Decimals, Fractions, and Percentages

  • Continually practicing conversions between the three forms can help to instil a deeper understanding of the relationship between decimals, fractions, and percentages.
  • When comparing and ordering these numbers, it’s usually easier to convert everything to decimals.
  • Regularly apply what you learn to real-world settings. For example, use percentages when figuring out discounts or markups, fractions for splitting items, and decimals in measurements.