Section 1.3 Fractions

Vocab The Numerator is the number on top The Denominator is the number on bottom The Factors of a number are those numbers that will divide into it evenly.

Simplifying (aka reducing to lowest terms) A fraction is simplified when the numerator and the denominator have no common factors. Simplify: 1) 20 2) 32 3) 245 55 80 350

Multiplying Multiply across the numerators and denominators. Reduce if possible. EX: Multiply 1) 6 · 7 2) 3 · 10 13 17 8 11

Dividing To divide, multiply by the RECIPROCAL In other words, FLIP the 2nd fraction and multiply. EX: Divide 1) 5 ÷ 10 2) 3 ÷ 30 11 17 8

Adding and Subtracting Before you can add or subtract, you must have a common denominator! Once both fractions are in terms of the LCD, add or subtract the numerators only. EX: Add or Subtract 1) 2 + 5 2) 7 - 3 3 7 12 8

Mixed Numbers Need to be written as improper fractions before you work with them! Multiply the denominator by the whole #, then add the numerator. (Write over the denominator). EX: