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Example 5-5b Objective Add and subtract decimals
Example 5-5b Review Vocabulary Evaluate Find the value of an expression by replacing variables with numerals
Lesson 5 Contents Example 1Add Decimals Example 2Subtract Decimals Example 3Annex Zeros Example 4Use Decimals to Solve a Problem Example 5Evaluate an Expression
Example 5-1a Find the sum of 75.6 and 21.3 Answer: 96.9 Add as with whole numbers Write the problem vertically with decimals lined up Put decimal in answer /5
Example 5-1b Find the sum of 34.6 and 53.2 Answer: /5
Example 5-2a Find – Answer: Subtract as with whole numbers – Put decimal in answer /5 Write the problem vertically with decimals lined up
Example 5-2b Find – Answer: /5
Example 5-3a Find 8 – 1.74 Answer: 6.26 Annex zeros 8.00 – – 1.74 Subtract as with whole numbers Put decimal in answer /5 Write the problem vertically with decimals lined up
Example 5-3b Find 9 – 3.28 Answer: /5
Example 5-4a PIZZA Joe’s Pizza Shop sells an average of 89.7 pizzas on Tuesday nights and an average of pizzas on Saturday nights. How many more pizzas does Joe’s Pizza Shop sell on Saturdays? – 89.7 Subtract 4/5 Determine a plan to solve the problem Write the problem vertically with decimals lined up Remember when subtracting: Big number - small number 210.5
Example 5-4a PIZZA Joe’s Pizza Shop sells an average of 89.7 pizzas on Tuesday nights and an average of pizzas on Saturday nights. How many more pizzas does Joe’s Pizza Shop sell on Saturdays? Answer: more pizzas on Saturdays. – / Put decimal in answer Subtract as with whole numbers
Example 5-4b MOVIES The local movie theater sells an average of 65.8 tickets on Thursdays and an average of tickets on Saturdays. How many more tickets are sold on Saturdays? Answer: tickets 4/5
Example 5-5a ALGEBRA Replace a with – 4.80 a - b Write equation 5/ Replace b with Bring down Write the problem vertically with decimals lined up Evaluate a - b if a = and b = 4.8
Example 5-5a ALGEBRA – a - b Answer: / Put decimal in answer Subtract as with whole numbers
Example 5-5b Answer: ALGEBRA * 5/5 Evaluate m + n if m = and n = 29.51
End of Lesson 5 Assignment Lesson 3:5 Adding and Subtracting Decimals All