EXAMPLE 1 Adding and Subtracting Decimals a

EXAMPLE 1 Adding and Subtracting Decimals a

EXAMPLE 1 Adding and Subtracting Decimals a

EXAMPLE 1 Adding and Subtracting Decimals a b. 8 – 1.65

EXAMPLE 1 Adding and Subtracting Decimals a b. 8 – –

EXAMPLE 1 Adding and Subtracting Decimals a b. 8 – –

EXAMPLE 1 Adding and Subtracting Decimals a b. 8 – c –

EXAMPLE 1 Adding and Subtracting Decimals a b. 8 – c –

EXAMPLE 1 Adding and Subtracting Decimals a b. 8 – c –

EXAMPLE 2 Evaluating Algebraic Expressions Evaluate when 20 x – x = 4.71.

EXAMPLE 2 Evaluating Algebraic Expressions Evaluate when 20 x – x = x = Substitute 4.71 for x. ––

EXAMPLE 2 Evaluating Algebraic Expressions Evaluate when 20 x – x = x = Substitute 4.71 for x. –– Subtract. = 15.29

Using Mental Math to Add Decimals Find the total cost for a sweet roll that costs $1.30, two hard rolls that cost $1.20 each, and a coffee cake that costs $3.70. EXAMPLE 3 Bakery costs

Using Mental Math to Add Decimals Find the total cost for a sweet roll that costs $1.30, two hard rolls that cost $1.20 each, and a coffee cake that costs $3.70. EXAMPLE 3 Bakery costs STEP 1 List the prices.

Using Mental Math to Add Decimals Find the total cost for a sweet roll that costs $1.30, two hard rolls that cost $1.20 each, and a coffee cake that costs $3.70. EXAMPLE 3 Bakery costs STEP 1 List the prices. $1.30 $1.20 $3.70

Using Mental Math to Add Decimals Find the total cost for a sweet roll that costs $1.30, two hard rolls that cost $1.20 each, and a coffee cake that costs $3.70. EXAMPLE 3 Bakery costs STEP 1 List the prices.STEP 2 Rearrange and group pairs of prices. $1.30 $1.20 $3.70

Using Mental Math to Add Decimals Find the total cost for a sweet roll that costs $1.30, two hard rolls that cost $1.20 each, and a coffee cake that costs $3.70. EXAMPLE 3 Bakery costs STEP 1 List the prices.STEP 2 Rearrange and group pairs of prices. $1.30 $1.20 $3.70 $1.30 $3.70 $1.20

Using Mental Math to Add Decimals Find the total cost for a sweet roll that costs $1.30, two hard rolls that cost $1.20 each, and a coffee cake that costs $3.70. EXAMPLE 3 Bakery costs STEP 1 List the prices.STEP 2 Rearrange and group pairs of prices. $1.30 $1.20 $3.70 $5$5 $1.30 $3.70 $1.20

Using Mental Math to Add Decimals Find the total cost for a sweet roll that costs $1.30, two hard rolls that cost $1.20 each, and a coffee cake that costs $3.70. EXAMPLE 3 Bakery costs STEP 1 List the prices.STEP 2 Rearrange and group pairs of prices. $1.30 $1.20 $3.70 $2.40 $1.30 $3.70 $1.20 $5$5

Using Mental Math to Add Decimals Find the total cost for a sweet roll that costs $1.30, two hard rolls that cost $1.20 each, and a coffee cake that costs $3.70. EXAMPLE 3 Bakery costs STEP 1 List the prices.STEP 2 Rearrange and group pairs of prices. $1.30 $1.20 $3.70 $7.40 $1.30 $3.70 $1.20 $5$5 $2.40

ANSWER Using Mental Math to Add Decimals Find the total cost for a sweet roll that costs $1.30, two hard rolls that cost $1.20 each, and a coffee cake that costs $3.70. EXAMPLE 3 Bakery costs STEP 1 List the prices.STEP 2 Rearrange and group pairs of prices. $1.30 $1.20 $3.70 $7.40 The bakery goods will cost $7.40. $1.30 $3.70 $1.20 $5$5 $2.40

Evaluate the expression when x=5.82 and y=9.1. GUIDED PRACTICE for Example 1, 2 and 3

GUIDED PRACTICE x = for Example 1, 2 and 3 Evaluate the expression when x=5.82 and y=9.1.

GUIDED PRACTICE x = = for Example 1, 2 and 3 Evaluate the expression when x=5.82 and y=9.1.

GUIDED PRACTICE x = = – y = 2. for Example 1, 2 and 3 Evaluate the expression when x=5.82 and y=9.1.

GUIDED PRACTICE x = = – y = – = 3.46 for Example 1, 2 and 3 Evaluate the expression when x=5.82 and y=9.1.

GUIDED PRACTICE x = = – y = – = y – x = for Example 1, 2 and 3 Evaluate the expression when x=5.82 and y=9.1.

GUIDED PRACTICE x = = – y = – = =3.28 for Example 1, 2 and 3 Evaluate the expression when x=5.82 and y=9.1. y – x = 9.1 – 5.82

GUIDED PRACTICE 4.Electronics Costs Find the total cost for a pair of headphones that costs $19.75, two compact disks that cost $11.50 each, and a pack of batteries that costs $4.25. for Example 1, 2 and 3

GUIDED PRACTICE The total cost is $47.ANSWER for Example 1, 2 and 3 4.Electronics Costs Find the total cost for a pair of headphones that costs $19.75, two compact disks that cost $11.50 each, and a pack of batteries that costs $4.25.