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5 Minute Check Complete in your notebook. 9 3 1. 10 + 5 2 1 2. 7 3 - 3 7 7 5 3. 9 8 - 2 6

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5 Minute Check Complete in your notebook. 9 3 1. 10 + 5

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5 Minute Check Complete in your notebook. 9 3 9 6 15 1 1. 10 + 5 = 10 + 10 = 10 = 1 2

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5 Minute Check Complete in your notebook. 2 1 2. 7 3 - 3 7

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5 Minute Check Complete in your notebook. 2 1 23 22 2. 7 3 - 3 7 = 3 - 7 7 x 23 22 x 3 7 x 3 - 7 x 3 161 66 95 11 21 - 21 = 21 = 4 21

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5 Minute Check Complete in your notebook. 7 5 3. 9 8 - 2 6

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5 Minute Check Complete in your notebook. 7 5 79 17 3. 9 8 - 2 6 = 8 - 6 3 x 79 17 x 4 3 x 8 - 6 x 4 237 68 169 1 24 - 24 = 24 = 7 24

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Monday, Oct 21 Lesson 4.1 Estimate Products of Fractions

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Objective: To understand how to estimate the product of fractions and /or whole numbers.

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Estimate Products of Fractions At the end of this lesson you should be able to answer the following question. Why is estimating products useful?

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Estimate Products of Fractions To multiply fractions, multiply the numerators and multiply the denominators, then simplify if needed. Example x = 3 2 6 3 4 x 5 = 20 = 10 x =

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Estimate Products of Fractions To multiply a fraction and whole number, convert the whole number to a fraction, then multiply as before. Example 2 5 x 14 x = 2 14 28 3 5 x 1 = 5 = 5 5 x =

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Estimate Products of Fractions There are three methods to use to estimate. Each method is used in a specific situation. Method 1 – Estimating the product of a fraction and whole number. Method 2 – Estimating the product of two fractions. Method 3 – Estimating the product of two mixed numbers.

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Estimate Products of Fractions 1. When estimating the product of a fraction and whole number use a comparable number for the whole number or the denominator (whichever is larger). The comparable number should be divisible by the smaller number.

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Estimate Products of Fractions Estimate: 1 4 x 13

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Estimate Products of Fractions Estimate: 1 4 x 13 Which number is larger?

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Estimate Products of Fractions Estimate: 1 4 x 13 What number is close to 13, but divisible by 4?

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Estimate Products of Fractions Estimate: 1 4 x 13 1 4 x 12

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Estimate Products of Fractions Estimate: 1 4 x 13 ≈ 3 1 12 12 4 x 1 = 4 = 3

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Estimate Products of Fractions 1 Estimate 4 x 13 ≈ 3 We can also make a model. 12 3333

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Estimate Products of Fractions Estimate: 1 7 x 3

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Estimate Products of Fractions Estimate: 1 7 x 3 Which number is larger?

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Estimate Products of Fractions Estimate: 1 7 x 3 What number is close to 7, but divisible by 3?

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Estimate Products of Fractions Estimate: 1 7 x 3 ≈ 2 1 3 3 1 6 x 1 = 6 = 2

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Estimate Products of Fractions 5 Estimate 6 x 13 (Do this on your own)

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Estimate Products of Fractions 5 Estimate 6 x 13 ≈ 10 5 12 60 6 x 1 = 6 = 10 12 222222

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Estimate Products of Fractions 2 Estimate 5 x 11 (Do this on your own)

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Estimate Products of Fractions 2 Estimate 5 x 11≈ 4 2 10 20 5 x 1 = 5 = 4

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Estimate Products of Fractions 2. When multiplying a fraction by a fraction, an estimate can be determined by rounding the fractions.

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Estimate Products of Fractions 2. When multiplying a fraction by a fraction, an estimate can be determined by rounding the fractions. Round up to 1 when the numerator is almost as large as the denominator. Example: 7/8 rounds up to 1

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Estimate Products of Fractions 2. When multiplying a fraction by a fraction, an estimate can be determined by rounding the fractions. Round up to 1 when the numerator is almost as large as the denominator. Round to ½ when the numerator is about half the denominator. Example: 3/7 rounds to 1/2

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Estimate Products of Fractions 2. When multiplying a fraction by a fraction, an estimate can be determined by rounding the fractions. Round up to 1 when the numerator is almost as large as the denominator. Round to ½ when the numerator is about half the denominator. Round down to zero when the numerator is much smaller than the denominator. Example: 1/5 rounds to 0

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Estimate Products of Fractions Can either be estimated up or down 0 ¼ ½ ¾ 1

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Estimate Products of Fractions Round the fraction. 3 5

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Estimate Products of Fractions Round the fraction. 3 1 5 ≈ 2 Since 3 is about half of 5, we round to ½.

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Estimate Products of Fractions Round the fraction. 1 9

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Estimate Products of Fractions Round the fraction. 1 9 ≈ 0 Since 1 is much less than 9, we round to 0.

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Estimate Products of Fractions Round the fraction. 9 10

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Estimate Products of Fractions Round the fraction. 9 10 ≈ 1 Since 9 is close to 10, we round to 1.

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Estimate Products of Fractions Estimate. 1 7 3 x 9 Round each fraction, then perform the operation.

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Estimate Products of Fractions Estimate. 1 7 3 x 9 1 2 x 1= 2

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Estimate Products of Fractions Estimate. 1 4 9 x 5

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Estimate Products of Fractions Estimate. 1 4 9 x 5 0 x 1= 0

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Estimate Products of Fractions 3. When estimating the product of two mixed numbers, round the mixed number to the nearest whole number. For example: 6 1 2 7 x 3 4 3 x 3= 9

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Estimate Products of Fractions Estimate: 1 5 3 8 x 1 6

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Estimate Products of Fractions Estimate: 1 5 3 8 x 1 6 3 x 2 = 6

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Estimate Products of Fractions Recap – When estimating a product of a fraction and whole number, choose a comparable number for the whole number or the denominator of the fraction (which ever is larger) which are in the same multiples list.

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Estimate Products of Fractions Recap – When estimating a product of two fractions round the fractions to 0, ½ or 1.

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Estimate Products of Fractions Recap – When estimating a mixed number round to the nearest whole number.

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Estimate Products of Fractions Why is estimating products useful?

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Estimate Products of Fractions Friday is the last day to turn in any missing assignments.

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Estimate Products of Fractions Agenda Notes Homework – Homework Practice 4-1 Due Tuesday, Oct 22 Mid Chapter 4 Quiz –Monday, Oct 28

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