Unit 5 Decimal Operations — Unit Plan

Title	Assessment
Lesson 3 Adding and Subtracting Decimals with Few Non-Zero Digits	Lesson 3 Cool-Down Find the value of each expression and show your reasoning. $1.56 + 0.083$ $0.2 - 0.05$ Show Solution 1.643. Sample reasoning: Six hundredths and 8 hundredths make 14 hundredths, or 1 tenth and 4 hundredths. The sum has 1 one, 6 tenths, 4 hundredths, and 3 thousandths. 0.15. Sample reasoning:
Lesson 4 Adding and Subtracting Decimals with Many Non-Zero Digits	Lesson 4 Cool-Down A runner has run 1.192 kilometers of a 10-kilometer race. How much farther does she need to run to finish the race? Show your reasoning. Show Solution 8.808 kilometers. Sample reasoning: $9.999 - 1.192 = 8.807$ . Adding 0.001 to 8.807 gives 8.808.
Section A Check Section A Checkpoint - Adding and Subtracting Decimals

Lesson 5 Using Fractions to Multiply Decimals	Lesson 5 Cool-Down Use what you know about decimals or fractions to explain why $(0.2) \boldcdot (0.002)= 0.0004$ . A rectangular plot of land is 0.4 kilometer long and 0.07 kilometer wide. What is its area in square kilometers? Show Solution Sample response: 0.2 is $\frac{2}{10}$ , and 0.002 is $\frac{2}{1,000}$ . Multiplying the two we have: $\frac{2}{10} \boldcdot \frac{2}{1,000} = \frac{4}{10,000}$ , which is 0.0004. 0.028 square kilometers, because $(0.4) \boldcdot (0.07)=0.028$
Lesson 8 Calculating Products of Decimals	Lesson 8 Cool-Down Calculate $(1.6) \boldcdot (0.215)$ . Show your reasoning. Show Solution 0.344. Sample reasoning:
Section B Check Section B Checkpoint - Multiplying Decimals

Lesson 10 Using Partial Quotients	Lesson 10 Cool-Down Calculate $4,235 \div 11$ using any method. Show Solution 385. Sample reasoning:
Lesson 12 Dividing Numbers that Result in a Decimal	Lesson 12 Cool-Down Use long division to find each quotient. Show your computation, and write your answer as a decimal. $43.5 \div 5$ $7 \div 8$ Show Solution 14.5 0.875
Lesson 13 Dividing a Decimal by a Decimal	Lesson 13 Cool-Down Write two division expressions that have the same value as $36.8 \div 2.3$ . Find the value of $36.8 \div 2.3$ . Show your reasoning. Show Solution Sample responses: $3.68 \div 0.23$ and $368 \div 23$ . 16. Sample reasoning:
Section C Check Section C Checkpoint - Dividing Decimals
Unit 5 Assessment Unit 5 Assessment - Decimal Operations	Problem 1 Find the product: $(0.061) \boldcdot (0.43)$ Show Solution 0.02623 Problem 2 Find the difference: Show Solution 0.5692 Problem 3 For part of a science experiment, Andre adds 0.25 milliliters of food coloring to 12.3 milliliters of water. How many milliliters does the mixture contain? A.12.05 B.12.325 C.12.55✓ D.14.8 Show Solution C Problem 4 Four runners are training for long races. Noah ran 5.123 miles, Andre ran 6.34 miles, Jada ran 7.1 miles, and Diego ran 8 miles. What is the total running distance of the four runners? Compared to Noah, how much farther did Jada run? Show Solution 26.563 miles 1.977 miles Problem 5 One way to compute a 15% tip for a bill is to multiply it by 0.15. A restaurant bill was $42.40. Calculate the tip. Explain or show your reasoning. Show Solution $6.36. Sample reasoning: I multiplied 42.40 by 0.1 to get 4.24 and then found half of that to get $(0.05) \boldcdot (42.40) = 2.12$ . Then I added the two answers to get $6.36. Problem 6 A woodworker wants to cut a board that is 8.225 feet long into 5 equal-length pieces. How long will each piece be? A. 0.1645 foot B. 1.645 feet C. 4.1125 feet D. 41.125 feet Show Solution 1.645 feet Problem 7 The list below shows the cost of the same candle at two different stores. Store ABC sells 6 of these candles for $12.00. Store XYZ sells 8 of these candles for $14.00. Which store sells the candle for a lower unit rate? Explain how you determined your answer. Problem 8 A diagram of a rectangular flag, with a shaded section, is shown below. What is the area, in square centimeters, of the shaded section of the flag? Show your work. Answer: ______ square centimeters Problem 9 A tutoring company charges $25.00 per hour to tutor a student. How many hours of tutoring would cost $62.50? A. $2\frac{1}{2}$ B. $3\frac{1}{2}$ C. $37\frac{1}{2}$ D. $87\frac{1}{2}$ Show Solution A