# 3.2 Estimating Decimal Products and Quotients g n i t a m i t s E

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r Mrs. F de Math En 5th Gra Lesson Objectives By the end of todays lesson you will be able to: 1)Estimate products using mental math. 2)Estimate quotients using compatible numbers.

Estimating Products Estimate each product. 1) 7.65 3.2 2) 6.43 4.7 Estimating Products Estimate each product. 3) 4.567.02

35 4) 6.39.2 54 5) 3.2958 180

Estimating Products Josh bought 3 yards of fabric to make a flag. Fabric costs \$5.35 per yard. The clerk says his total is \$14.95 before tax. Did the clerk make a mistake? Estimating Products You buy 24 donuts from the Donut Emporium

in Plano. Each donut costs \$.98 . Estimate the cost before tax for 2 dozen donuts? \$24 Objective #1 Can you ~ estimate products using mental math? Lets Check

Check for Understanding Estimating Quotients 63=2 The first number is the dividend. The second number is the divisor. The number after the = sign is the quotient.

Estimating Quotients Name the following: 18 3 = 6 3 is the: 18 is the: 6 is the: Estimating Quotients defn: compatible numbers: -numbers easy to divide mentally

*When dividing, you can use compatible numbers to estimate quotients Estimating Quotients When you estimate the quotient: 1)Round the divisor. 2)Round the dividend to a compatible number. Estimating Quotients

Estimate the quotient using compatible numbers. 1) 14.9 2.8 2) 25.3 4.9 Estimating Quotients Estimate the quotient using compatible

numbers. 3) 35.83.8 9 4) 29.41.8 15 5) 49.64.4

10 Estimating Quotients The cost to ship 1 yearbook is \$3.12. The total cost for a shipment was \$62.40. Estimate how many books were in the shipment. 1) Round the divisor. 2) Round to a multiple of 3. 3) Find the quotient.

Estimating Quotients Use estimation. Is each quotient reasonable? 1) 17.9318.34 =2.15 31.4235.94=3.29 2) Estimating Quotients

Use estimation. Is each quotient reasonable? 3) 318.2744.07=78.2 4) 41.096.88=5.12 Reasonable Not Reasonable Objective #2 Can you ~ estimate quotients using compatible numbers?

Lets Check Check for Understanding Next, compare answers with a neighbor. 18) 5 19) 6 21) 15

Estimating Decimal Products and Quotients Ask yourself if you can do the following: 1)Estimate products using mental math. 2)Estimate quotients using compatible numbers.