Day 4:~ Multiply & Divide Integers,

Fractions, and Decimals~ Estimation, Square Roots, and

the Number Line

Objectives

• I can multiply and divide integers• I can multiply and divide decimals• I can multiply and divide fractions

Warm-Up

1. 2. 3.

4. 5. 6.

7. 3.142 + 12.7 8. 16.75 – 8.318

Rules for Multiplying and Dividing Integers

(neg) (neg) = (pos)(-) (-) = (+)

And

(neg) (pos) = (neg)(-) (+) = (-)(+) (-) = (-)

Rules continued

When the signs are the SAME, answer is

____________________

When the signs are DIFFERENT, answer is

____________________

Examples

1) (-7) (-8) 2. 12 ÷ (-4)

3. Billy casually bet Sammy that the Dodgers were going to beat the Angels in the next game. Billy already owed Sammy $5 (_____), if Billy bet, “double or nothing” with Sammy, how much could Billy potentially loos to Sammy if the Dodgers loose?

Try

4. 6 (-4)

5. (-42) ÷ (-6)

6. (-36) ÷ 4

Multiply Fractions

The word _______ also means multiply.

7) So, what is half of 6?

8) What is a quarter of 8?

How do you multiply fractions when they aren’t this easy? What are the rules/steps?

Multiplying Fractions Steps:9.

10.

11. What happens if a fraction is negative?

Try

12. 13.

14. You babysit for hours each week. How many hours do you babysit in a month?

Dividing Fractions

Multiply by the ____________________

Step 1: Keep 1st termStep 2: Change to multiplicationStep 3: Flip the 2nd termStep 4: Multiply fractions as usual

Examples

15)

16) How many t-shirts can be made with 16 yds of fabric if each t-shirt rquires yds?

Try

17)

18) How many 9 inch ribbons can be cut from yds of ribbon? (**Remember … 12 in = 1 ft and 1 yd = 3 ft)

Multiplying Decimals

Multiply as if they were whole numbers (DO NOT NEED TO LINE UP DECIMALS). Count how many numbers are after decimals and move that many places in the final answer Same rules apply for positives and negatives

Example

19) 13.2 × (-0.24)

Try

20) 5.8 × (-4.2)

Dividing Decimals

Copy problem down as you would for whole numbers

You cannot divide by a decimal number, so move the decimal point in the divisor until it becomes a whole number

Move the decimal point in the dividend that same amount of places. Using zeros when necessary

Copy the decimal point form the dividend straight above in the place for the answer

Same rules apply for positives and negatives

Example

21) (-374.5) ÷ 0.07

Try

22) 18.46 ÷ 1.3

Try

23) $1125.25 ÷ 0.75

Objectives and Standard

• I can correctly order fractions, decimals, and irrational numbers from least to greatest.

• I can compare fractions and decimals• I can estimate radicals to their largest whole

numbers

14.6 NF Understand decimal notation for fractions, and compare decimals and fractions

Quick Review

Convert:1. to a decimal.

2. 0.35 to a fraction

3. to a decimal and then estimate

Comparing Fractions and Decimals

Write the Correct Comparison Symbol ( >, <, or = ).

1. ___ 0.483 2. ___ 0.827

Estimating Square Roots

Estimate .

Estimate .

Ordering Numbers

Example:Put in order from least to greatest., , ,

Ordering Numbers

Try:Put in order from least to greatest., , ,

Homework

Day 4 WorksheetStudy for Unit 1 Test – Review all notes!!