Engage NY Module 1 Lesson 5 Objective: Name decimal fractions in expanded, unit, and word forms by applying place value reasoning.

MULTIPLY AND DIVIDE BY EXPONENTS Write 54 tenths as a decimal. Say the decimal. Multiply it by 10². Say the product. 5.4 x 10² = 540

MULTIPLY AND DIVIDE BY EXPONENTS Write 6 tenths as a decimal. Say the decimal. Multiply it by 10². Say the product. 0.6 x 10² = 60

MULTIPLY AND DIVIDE BY EXPONENTS Write 6 tenths as a decimal. Say the decimal. Divide it by 10². Say the quotient. 0.6 ÷10² = 0.006

MULTIPLY AND DIVIDE BY EXPONENTS Write 2 and seven hundred eighty-four thousandths as a decimal. 2.784 Multiply it by 10³. Say the product. 2.784 x 10³ = 2784 Write six thousand five hundred eighty three. 6583 Divide it by 10³. Say the quotient. 6583 ÷ 10³ = 6.583

MULTIPLYING METRIC UNITS 3 3 3 m = ____ cm Show 3 in your place value chart. How many centimeters are in 1 meter? Show how many centimeters are in 3 meters on your place value chart. 3 m = 300 cm

MULTIPLYING METRIC UNITS 7 7 7 kg = ____ g Show 7 in your place value chart. How many grams are in 1 kilogram? Show how many grams are in 7 kilograms on your place value chart. 7 kg = 7000 g

MULTIPLYING METRIC UNITS 7 7 7000 ml = ____ l Show 7000 in your place value chart. How many milliliters are in 1 liter? Show how many liters are in 7000 milliliters on your place value chart. 7000 ml = 7 l

MULTIPLYING METRIC UNITS 7 5 7 5 7500 m = ____ km ____ m Show 7500 in your place value chart. How many meters are in 1 km? Show how many kilometers are in 7500 meters on your place value chart. 7500 m = 7 km 500 m 7

MULTIPLYING METRIC UNITS 8350 g = ____ kg ____ g Show 8350 in your place value chart. How many grams are in 1 kilogram? Show how many kilograms are in 8350 grams on your place value chart. 8350 g = 8 kg 350 g 7

APPLICATION PROBLEM Jordan measures a desk at 200 cm. James measures the same desk in millimeters, and Amy measures the same desk in meters. What is James’ measurement in millimeters? What is Amy’s measurement in meters? Show your thinking using a place value mat or an equation with exponents. Include a statement of solution. James: 200 cm = ____ mm 2000 mm Amy: 200 cm = ____ m 2 m 7

CONCEPT DEVELOPMENT Three thousand forty seven Write this number in standard form, expanded form, and unit form. Standard form: 3,047 Expanded form: 3,000 + 40 + 7 Unit form: 3 thousand, 4 tens, 7 ones Explain to your partner the purpose of writing this number in these different forms. 7

CONCEPT DEVELOPMENT – Problem 1 1 Write one thousandth using digits on your place value chart. How many ones, tenths, hundredths, thousandths? This is the standard form of the decimal for 1 thousandth. 7

CONCEPT DEVELOPMENT – Problem 1 We write 1 thousandth as a fraction like this. 𝟏 𝟏𝟎𝟎𝟎 1 thousandth is a single copy of a thousandth. I can write the expanded form using a fraction like this, 1 x ( 𝟏 𝟏𝟎𝟎𝟎 ) or using a decimal like this 1 x 0.001. The unit form of this decimal looks like this 1 thousandth. We use a numeral (1) and the unit (thousandth) written as a word for the unit form. One thousandth = 0.001 = 𝟏 𝟏𝟎𝟎𝟎 𝟏 𝟏𝟎𝟎𝟎 = 1 x ( 𝟏 𝟏𝟎𝟎𝟎 ) 0.001 = 1 x 0.001 1 thousandth 7

CONCEPT DEVELOPMENT – Problem 1 Imagine 3 copies of 1 thousandths. How many thousandths is that? Write in standard form and as a fraction. Standard form: 0.003 Fraction form: 𝟑 𝟏𝟎𝟎𝟎 3 thousandths is 3 copies of 1 thousandth, turn and talk to your partner about how this would be written in expanded form using a fraction and using a decimal. Three thousandths = 0.003 = 𝟑 𝟏𝟎𝟎𝟎 𝟑 𝟏𝟎𝟎𝟎 = 3 x ( 𝟏 𝟏𝟎𝟎𝟎 ) 0.003 = 3 x 0.001 3 thousandths 7

CONCEPT DEVELOPMENT – Problem 2 Write thirteen thousandths in standard form, and expanded form using fractions and then using decimals. Turn and share with your partner. Standard form: 0.013 Expanded forms: 1 x ( 𝟏 𝟏𝟎𝟎 ) + 3 x ( 𝟏 𝟏𝟎𝟎𝟎 ) 1 x 0.01 + 3 x 0.001 Now write this decimal in unit form. 1 hundredth 3 thousandths = 13 thousandths Thirteen thousandths = 0.013 = 𝟏𝟑 𝟏𝟎𝟎𝟎 𝟏𝟑 𝟏𝟎𝟎𝟎 = 0.013 = 1 x 0.01 + 3 x 0.001 1 hundredth 3 thousandths 13 thousandths 7

CONCEPT DEVELOPMENT – Problem 2 Write two hundred seventy-three thousandths in standard form, and expanded form using fractions and then using decimals. Standard form: 0.273 Expanded forms: 2 x ( 𝟏 𝟏𝟎 ) + 7 x ( 𝟏 𝟏𝟎𝟎 ) + 3 x ( 𝟏 𝟏𝟎𝟎𝟎 ) 2 x 0.1 + 7 x 0.01 + 3 x 0.001 Now write this decimal in unit form. 2 tenths 7 hundredths 3 thousandths = 2 tenths 73 thousandths = 27 hundredths 3 thousandths = 273 thousandths Two hundred seventy three thousandths = 0.273 = 𝟐𝟕𝟑 𝟏𝟎𝟎𝟎 𝟐𝟕𝟑 𝟏𝟎𝟎𝟎 = 0.273 = 2 x 0.1 + 7 x 0.01 + 3 x 0.001 2 tenths 7 hundredths 3 thousandths 273 thousandths 7

CONCEPT DEVELOPMENT – Problem 2 Write one and six hundred eight thousandths in standard form, and expanded form using fractions and then using decimals. Standard form: 1.608 Expanded forms: 1 + 6 x ( 𝟏 𝟏𝟎 ) + 8 x ( 𝟏 𝟏𝟎𝟎𝟎 ) 1 + 6 x 0.1 + 8 x 0.001 Now write this decimal in unit form. 1 one 6 tenths 8 thousandths = 1 one 60 hundredths 8 thousandths = 1 one 608 thousandths One and six hundred eight thousandths= 1.608 = 1 𝟔𝟎𝟖 𝟏𝟎𝟎𝟎 1 𝟔𝟎𝟖 𝟏𝟎𝟎𝟎 = 1.608 = 1 + 6 x 0.1 + 8 x 0.001 1 one 6 tenths 8 thousandths = 1 one 60 hundredths 8 thousandths = 1 one 608 thousandths 7

CONCEPT DEVELOPMENT – Problem 3 Write 25.413 in word form. Twenty-five and four hundred thirteen thousandths Now write this decimal in unit form. 2 tens 5 ones 4 tenths 1 hundredth 3 thousandths What are other unit forms of this number? 25 ones 413 thousandths 254 tenths 13 hundredths 25,413 thousandths Write it as a mixed number, then in expanded form. Twenty-five and four hundred thirteen thousandths= 25.413 = 25 𝟒𝟏𝟑 𝟏𝟎𝟎𝟎 25 𝟒𝟏𝟑 𝟏𝟎𝟎𝟎 = 2 x 10 + 5 x 1 + 4 x 𝟏 𝟏𝟎 + 1 x 𝟏 𝟏𝟎𝟎 + 3 x 𝟏 𝟏𝟎𝟎𝟎 25.413 = 2 x 10 + 5 x 1 + 4 x 0.1 + 1 x 0.01 + 3 x 0.001 2 tens 5 ones 4 tenths 1 hundredths 3 thousandths 25 ones 413 thousandths 7

CONCEPT DEVELOPMENT – Problem 3 Write 12.04 in word form. Twelve and four hundredths Now write this decimal in unit form. 1 ten 2 ones 4 hundredths What are other unit forms of this number? 12 ones 4 hundredths 1, 204 hundredths Write it as a mixed number, then in expanded form. Twelve and four hundredths= 12.04 = 12 𝟒 𝟏𝟎𝟎 12 𝟒 𝟏𝟎𝟎 = 1 x 10 + 2 x 1 + 4 x 𝟏 𝟏𝟎𝟎 12.04 = 1 x 10 + 2 x 1 + 4 x 0.01 1 ten 2 ones 4 hundredths = 12 ones 4 hundredths = 1,204 hundredths 7

CONCEPT DEVELOPMENT – Problem 3 Write 9.495 in word form. Nine and four hundred ninety-five thousandths Now write this decimal in unit form. 9 ones 4 tenths 9 hundredths 5 thousandths Write it as a mixed number, then in expanded form. Nine and four hundred ninety-five thousandths = 9.495 = 9 𝟒𝟗𝟓 𝟏𝟎𝟎𝟎 9 𝟒𝟗𝟓 𝟏𝟎𝟎𝟎 = 9 x 1 + 4 x 𝟏 𝟏𝟎 + 9 𝟏 𝟏𝟎𝟎 + 5 𝟏 𝟏𝟎𝟎𝟎 9.495 = 9 x 1 + 4 x 0.1 + 9 x 0.01 + 5 x 0.001 9 ones 4 tenths 9 hundredths 5 thousandths = 9,495 thousandths 7

CONCEPT DEVELOPMENT – Problem 4 Write four hundred four thousandths in standard form. 0.404 Now write four hundred and four thousandths in standard form. 400.004 Tell the digits you used to write four hundred four thousandths. How did you know where to write the decimal in each of the standard forms? Now write the expanded and unit forms for each of these numbers. Four hundred four thousandths = 0.404 = 𝟒𝟎𝟒 𝟏𝟎𝟎𝟎 = 4 x ( 𝟏 𝟏𝟎 ) + 4 ( 𝟏 𝟏𝟎𝟎𝟎 ) 0.404= 4 x 0.1 + 4 x 0.001 4 tenths 4 thousandths Four hundred and four thousandths = 400 𝟒 𝟏𝟎𝟎𝟎 = 4 x 100 + 4 ( 𝟏 𝟏𝟎𝟎𝟎 ) = 400.004 = 4 x 100 + 4 x 0.001 4 hundreds and 4 thousandths 7

CONCEPT DEVELOPMENT – Problem 4 Write two hundred two thousandths in standard form. 0.202 Now write nine hundred nine tenths in standard form. 900.9 How did you know where to write the decimal in each of the standard forms? Now write the expanded and unit forms for each of these numbers. Two hundred two thousandths = 0.202 = 𝟐𝟎𝟐 𝟏𝟎𝟎𝟎 = 2 x ( 𝟏 𝟏𝟎 ) + 2 ( 𝟏 𝟏𝟎𝟎𝟎 ) 0.202= 2 x 0.1 + 2 x 0.001 2 tenths 2 thousandths Nine hundred and nine tenths = 900 𝟗 𝟏𝟎𝟎𝟎 = 9 x 100 + 9 ( 𝟏 𝟏𝟎 ) = 900.9 = 9 x 100 + 9 x 0.1 9 hundred and 9 tenths 7