To add and subtract fractions with unlike denominators, first find a common denominator using one of these methods: Method 1 Find a common denominator by multiplying the two denominators. Method 2 Find the least common denominator(LCD) of the denominators. (Cake Method)
Steps • Find LCD or CD • Write equivalent fractions: Multiply the fraction by a value of 1 in order to get the LCD or CD • Add or subtract the numerators • Reduce
Write in Simplest form: • LCD: 18 • Rename Fractions: • Add the numerators:
Write the answer in simplest form. Find a common denominator: 4(5) = 20. Multiply by fractions equal to 1. + Rewrite with common denominators. Add numerators. Keep the denominator. Rewrite as a mixed number.
Find the perimeter of the figure below. + First, work with the fractions. Then, work with the whole numbers. Last, simplify.
Vickie has cups of shredded cheese to put in her enchilada casserole and ¾ cup of cheese for the top. If she has 3 cups of cheese in all, how much cheese will she have left?
Homework: • Page 129 (14-46) even