Decimals Grade 3 Copyright Ed 2 Net Learning

Fractions and Decimals n Decimal: A number that uses placevalue and a decimal point

$Tenths n n You can use fraction or a decimal to name parts of$

Tenths Grid Fraction or Mixed Number Decimal 1. 2 Word Name One and two

Hundredths n Hundredth: one of 100 equal parts of a whole Hundredths Grid Fraction

Hundredths Grid Fraction Decimal 1. 07 Word Name One and seven hundredths Remember: 100/100

Equivalent Decimals that name the same number are called equivalent decimals. ones 0 tenths

Compare & Order Decimals n n n Compare 2. 32 and 2. 26 Use

Compare & Order Decimals n n Compare 2. 32 and 2. 26 Use Models

Compare & Order Decimals n n Order 3. 47, 2. 26, 3. 75 Use

Add Decimals n n Use models Add 0. 5 + 0. 7 ¡ ¡

Add Decimals n n You can also add decimals greater than 1. Add 1.

Add Decimals n n n Use Place Value Example: Add 0. 5 + 0.

Add Decimals n Step 2: Add the ones next. Write the decimal point in

Subtract Decimals n n Use models Subtract 1. 2 – 0. 5 ¡ ¡

Subtract Decimals n n Use models to subtract decimals with hundredths Subtract 0. 68

Subtract Decimals n n n Use Place Value Example: 1. 12 – 0. 35

Subtract Decimals n Step 2: Subtract the tenths next. Regroup if needed. 0 10

Subtract Decimals n Step 3: Subtract the ones next. 0 10 0 12 1.

Connecting Decimals and Money 100 pennies = $1. 00 1 ₵ = 1/100 of

Connecting Decimals and Money 5 ₵ = 5/100 of a dollar 5 cents is

Connecting Decimals and Money 10 dimes = $1. 00 1 ₵ = 10/100 of

Connecting Decimals and Money 1 dime = 10 ₵ = 1/10 of a dollar

Connecting Decimals and Money Use Place Value ones 2 tenths . 3 hundredths 5

Let us take a break! Copyright © Ed 2 Net Learning, Inc. 27

$Assessment 1. Write the fraction and the decimal to name each shaded part. Copyright$

$Assessment 2. Write the fraction and the decimal to name each shaded part. Copyright$

Assessment 3. 4. 5. 6. 7. 8. 9. 10. Write “sixty-five hundredths” as a

Great Job! n Remember to do the practice sheets!! Copyright © Ed 2 Net

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Fractions and Decimals n Decimal: A number that uses placevalue and a decimal point to show tenths and hundredths, and so on. ¡ n Examples: $0. 25, $0. 50, $0. 75 A decimal point is a period separating the ones and the tenths in a decimal. Copyright © Ed 2 Net Learning, Inc. 2

$Tenths n n You can use fraction or a decimal to name parts of$

Tenths n n You can use fraction or a decimal to name parts of a whole. Tenth: one of 10 equal parts of a whole Tenths Grid Fraction Decimal Word Name 0. 4 Four tenths Copyright © Ed 2 Net Learning, Inc. 3

Hundredths n Hundredth: one of 100 equal parts of a whole Hundredths Grid Fraction Decimal 0. 40 Word Name Forty hundredths Remember: 10/100 = 1/10; So, 0. 4 = 0. 40; four tenths = forty hundredths Copyright © Ed 2 Net Learning, Inc. 5

Equivalent Decimals that name the same number are called equivalent decimals. ones 0 tenths . 5 hundredths 0 fifty hundredths ones 0 tenths . hundredths 5 Five tenths Copyright © Ed 2 Net Learning, Inc. 7

Compare & Order Decimals n n n Compare 2. 32 and 2. 26 Use Place Value Line up the decimal points. Compare each place, starting at the greatest place. 2. 3 2 2. 2 6 2. 32 > 2. 26 2=2 3>2 Copyright © Ed 2 Net Learning, Inc. 8

Compare & Order Decimals n n Order 3. 47, 2. 26, 3. 75 Use a number line 2. 26 2 3. 47 2. 1 2. 2 2. 3 2. 4 2. 5 2. 6 2. 7 2. 8 2. 9 3 2. 26 < 3. 47 3. 75 3. 1 3. 2 3. 3 3. 4 3. 5 3. 6 3. 7 3. 8 3. 9 4 2. 26 < 3. 75 Copyright © Ed 2 Net Learning, Inc. 3. 47 < 3. 75 11

Compare & Order Decimals n n Order 3. 47, 2. 26, 3. 75 Use Place Value Step 1 Line up the decimal points. Compare the greatest place first. 3. 47 2. 26 3. 75 Step 2 Compare the next greatest place. Step 3 Order the decimals from least to greatest. 3. 47 3. 75 2. 26, 3. 47, 3. 75 Think: 2 < 3 Think: 4 < 7 So, 2. 26 is the least. So, 3. 47 < 3. 75. Copyright © Ed 2 Net Learning, Inc. 12

Add Decimals n n Use models Add 0. 5 + 0. 7 ¡ ¡ 0. 5 + First shade one addend. Then shade the next addend. Find the total. So, 0. 5 + 0. 7 = 1. 2 Copyright © Ed 2 Net Learning, Inc. 0. 7 = 1. 2 Start shading the second addend right after the first addend. 13

Add Decimals n n You can also add decimals greater than 1. Add 1. 18 + 1. 23 ¡ ¡ First shade one addend. Then shade the next addend. Find the total. So, 1. 18 + 1. 23 = 2. 41 1. 18 + 1. 23 Copyright © Ed 2 Net Learning, Inc. = 2. 41 14

Add Decimals n n n Use Place Value Example: Add 0. 5 + 0. 9 Step 1: Line up the decimal points. Add the tenths as you would do the whole numbers. Regroup if necessary. 1 0. 5 + 0. 9 4 Copyright © Ed 2 Net Learning, Inc. 15

Subtract Decimals n n Use models to subtract decimals with hundredths Subtract 0. 68 – 0. 15 ¡ ¡ First shade 0. 68 Then take away 0. 15 Find how many are left. So, 0. 68 – 0. 15 = 0. 53 Copyright © Ed 2 Net Learning, Inc. 18

Subtract Decimals n n n Use Place Value Example: 1. 12 – 0. 35 Step 1: Line up the decimal points. Subtract the hundredths first. Regroup if needed. 0 12 1. 12 - 0. 35 7 Copyright © Ed 2 Net Learning, Inc. 19

Connecting Decimals and Money Use Place Value ones 2 tenths . 3 hundredths 5 $2. 35 to two dollars and thirty-five cents Remember: 100 pennies = 1 dollar; 1 penny = 1/100 = 0. 01 10 dimes = 1 dollar; 1 dime = 1/10 = 0. 01 4 quarters = 1 dollar; 1 quarter = 25/100 = 0. 25 Copyright © Ed 2 Net Learning, Inc. 26

$Assessment 1. Write the fraction and the decimal to name each shaded part. Copyright$

$Assessment 2. Write the fraction and the decimal to name each shaded part. Copyright$

Assessment 3. 4. 5. 6. 7. 8. 9. 10. Write “sixty-five hundredths” as a decimal. Write “one and seven tenths” as a decimal. Find 2. 9 + 4. 2 Find 9. 4 – 8. 3 Find 3. 6 + 4. 5 Find 7. 4 – 3. 9 Jeri ran the 40 -yard dash in 6. 4 seconds. Bo ran it in 9. 3 seconds. How many seconds faster was Jeri than Bo? Find 32/100 of $1. 00 Copyright © Ed 2 Net Learning, Inc. 31