Holt CA Course Adding and Subtracting Mixed Numbers NS2.1 Solve problems involving addition, subtraction, multiplication, and division of positive fractions and explain why a particular operation was used for a given situation. Also covered: NS2.4 California Standards

Holt CA Course Adding and Subtracting Mixed Numbers Add. Write the answer in simplest form. Teacher Example 1: Adding Mixed Numbers Find a common denominator. = = Add the integers, and then add the fractions. Add. =

Holt CA Course Adding and Subtracting Mixed Numbers Add. Write the answer in simplest form. Student Practice 1: Find a common denominator. = = Add the integers, and then add the fractions. Add. =

Holt CA Course Adding and Subtracting Mixed Numbers Remember! Any fraction in which the numerator and denominator are the same nonzero number is equal to 1.

Holt CA Course Adding and Subtracting Mixed Numbers Teacher Example 2: Subtracting Mixed Numbers Subtract. Write the answer in simplest form – – = 8989 – Find a common denominator. = Subtract the integers, and then subtract the fractions.

Holt CA Course Adding and Subtracting Mixed Numbers Student Practice 2: Subtract. Write the answer in simplest form – – = 7878 – Find a common denominator. = Subtract the integers, and then subtract the fractions.

Holt CA Course Adding and Subtracting Mixed Numbers Sometimes when you subtract mixed numbers, the fraction portion of the first number is less than the fraction portion of the second number. In these cases, you must regroup before subtracting. REGROUPING MIXED NUMBERS WORDS NUMBERS = = = Rewrite 1 as a fraction with a common denominator. Regroup. Add.

Holt CA Course Adding and Subtracting Mixed Numbers Subtract. Write the answer in simplest form. Teacher Example 3: Subtracting Mixed Numbers – – 12 = – Regroup = Subtract the integers, and then subtract the fractions. Simplify. = =

Holt CA Course Adding and Subtracting Mixed Numbers Subtract. Write the answer in simplest form. Student Practice 3: – – 10 = – Regroup = Subtract the integers, and then subtract the fractions. Simplify. = =3 1212

Holt CA Course Adding and Subtracting Mixed Numbers Teacher Example 3: Measurement Application Kevin is 48 inches tall. His brother Keith is inches taller. How tall is Keith? = Add the integers, and then add the fractions. = Rewrite 8888 as 1. Keith is 54 inches tall. Estimate = Round 3838 to and to equals 54, so the answer is reasonable.

Holt CA Course Adding and Subtracting Mixed Numbers Student Practice 3: Alvin weighs 72 lbs. His baby brother weighs 15 lbs. How much do they weigh together? = Add the integers, and then add the fractions. = Rewrite 3333 as 1. Together they weigh 88 pounds Estimate = Round 72 to 73 and 15 to equals 88, so the answer is reasonable.