5 Minute Check Complete in your notebook. Find each sum 1. 4.9 + 3.0 2. 0.796 + 13 Find the difference. 3. 19.86 - 4.94 4. 82 – 67.18

Tuesday, Oct 30

5 Minute CheckComplete in your notebook. Find each sum1. 4.9 + 3.02. 0.796 + 13Find the difference.3. 19.86 - 4.944. 82 67.185 Minute CheckComplete in your notebook. Find each sum1. 4.9 + 3.05 Minute CheckComplete in your notebook. Find each sum1. 4.9 + 3.0 4.9 + 3.0 7.95 Minute CheckComplete in your notebook. Find each sum2. 0.796 + 135 Minute CheckComplete in your notebook. Find each sum2. 0.796 + 13 13.000 Annex zeros, if needed. + 0.796 13.7965 Minute CheckComplete in your notebook. Find the difference.3. 19.86 - 4.945 Minute CheckComplete in your notebook. Find the difference.3. 19.86 - 4.94

19.86 - 4.94 14.925 Minute CheckComplete in your notebook. Find the difference.4. 82 67.185 Minute CheckComplete in your notebook. Find the difference.4. 82 67.18

82.00 Annex zeros - 67.18 14.82Accum Rev 2What two things must a unit rate have?Monday, Sept 22Lesson 6.3.3

Multiplying Decimals by Whole NumbersMultiplying Decimals by Whole NumbersLesson 6.3.2 is estimation and will be incorporated into lessons 6.3.3 and 6.3.4.

Multiplying Decimals by Whole NumbersObjective: To understand how to estimate and find products of decimals and whole numbers.

Multiplying Decimals by Whole NumbersTo multiply a decimal and whole number, multiply as normal and then place the decimal point.

Multiplying Decimals by Whole NumbersFind the product of 4 and .83.

First, round the numbers to the nearest whole number to get an estimate.

What does .83 round to?

Digits from 0 to 4 round down and digits from 5-9 round up.


First, round the numbers to the nearest whole number to get an estimate.

What does .83 round to? 1

4 x 1 = 4, so4 x .83 4

Multiplying Decimals by Whole NumbersFind the product of 4 and .83.To Multiply Decimals.Step 1 Stack the numbers with the number with the most digits on top.

Multiplying Decimals by Whole NumbersFind the product of 4 and .83.To Multiply Decimals.Step 1 Stack the numbers with the number with the most digits on top. .83 x 4

Multiplying Decimals by Whole NumbersFind the product of 4 and .83.To Multiply Decimals.Step 2 Multiply the digits without regard to the decimal place.

Multiplying Decimals by Whole NumbersFind the product of 4 and .83.To Multiply Decimals.Step 2 Multiply the digits without regard to the decimal place. .83 x 4 332

Multiplying Decimals by Whole NumbersFind the product of 4 and .83.To Multiply Decimals.Step 3 Determine the number of decimal places in the factors to locate the decimal place in the product.

Multiplying Decimals by Whole NumbersFind the product of 4 and .83.To Multiply Decimals.Step 3 Determine the number of decimal places in the factors to locate the decimal place in the product. .83 2 decimal places x 4 0 decimal places 3.32 2 decimal places

Is this a reasonable answer?



3.32 4


Another way of thinking about this is by adding four groups of .83.

Multiplying Decimals by Whole NumbersFind the product of 3 and 14.2.

Remember, this is just..


Estimate?


Estimate?

3 x 14 = 42

Step 1 - ?


3 x 14.2


14.2 x 3

Step 2 - ?


14.2 x 3 426

Step 3 - ?


14.2 1 decimal place x 3 42.6 1 decimal place

Does this seem reasonable?


14.2 1 decimal place x 3 42.6 1 decimal place

Does this seem reasonable?

42.6 42


(Do this on your own)



Estimate ?


Estimate ?4 x 1 = 4

Actual product?


.95 2 decimal places x 4 3.80 2 decimal places

Does this sound reasonable?


.95 2 decimal places x 4 3.80 2 decimal places

Does this sound reasonable?3.8 4




Estimate?


Estimate?

2 x 0 = 0

Actual product?


.018 3 decimal places x 2.036 3 decimal places

Make sure you multiply the zeros. You may need them later.






Does this sound reasonable?.036 0


2 x 0.18 0.018 x 2.036

All answers on the homework will need the estimate and a circled actual answer.




Estimate?


Estimate?

4 x 0 = 0

Actual product?


0.0027 4 decimal places x 4 0.0108 4 decimal places


Multiplying Decimals by Whole NumbersFind the product of 4 and 0.0027.4 x 0.0027 0 0.0027 x 4 0.0108

Multiplying Decimals by Whole NumbersA sheet of printer paper is 8.5 inches by 11 inches. What is the area of the paper? (Hint: area = length x width)



Estimate?


Estimate?

9 x 11 = 99

Actual answer?


8.5 1 decimal place x 1185 +85 0 93.5 1 decimal place



8.5 1 decimal place x 1185 +85 0 93.5 1 decimal place

Is this a reasonable answer? 93.5 99

Multiplying Decimals by Whole NumbersA sheet of printer paper is 8.5 inches by 11 inches. What is the area of the paper? (Hint: area = length x width)8.5 x 11 998.5 x 1185 +85 0 93.5

Multiplying Decimals by Whole NumbersA batch of trail mix calls for 1.2 pounds of dry cereal. Kyle is making 5 batches of trail mix. He already has 2 pounds of dry cereal. How many more pounds of dry cereal does he need?


Multiplying Decimals by Whole NumbersA batch of trail mix calls for 1.2 pounds of dry cereal. Kyle is making 5 batches of trail mix. He already has 2 pounds of dry cereal. How many more pounds of dry cereal does he need? Estimate?

Multiplying Decimals by Whole NumbersA batch of trail mix calls for 1.2 pounds of dry cereal. Kyle is making 5 batches of trail mix. He already has 2 pounds of dry cereal. How many more pounds of dry cereal does he need? Estimate? 1 x 5 = 55 2 = 3Actual answer?

Multiplying Decimals by Whole NumbersA batch of trail mix calls for 1.2 pounds of dry cereal. Kyle is making 5 batches of trail mix. He already has 2 pounds of dry cereal. How many more pounds of dry cereal does he need? 1.2 1 decimal placex 5 6.0 1 decimal place

6 lbs (what he needs) 2 lbs (he has) = 4 lbsIs this a reasonable answer?

Multiplying Decimals by Whole NumbersA batch of trail mix calls for 1.2 pounds of dry cereal. Kyle is making 5 batches of trail mix. He already has 2 pounds of dry cereal. How many more pounds of dry cereal does he need? 1.2 1 decimal placex 5 6.0 1 decimal place

6 lbs (what he needs) 2 lbs (he has) = 4 lbsIs this a reasonable answer? 4 3

Multiplying Decimals by Whole NumbersThe table shows the number of gallons of gasoline the Beckleys purchased on their road trip. What was the total cost for gasfor the trip?

Do this on your own.

Multiplying Decimals by Whole NumbersThe table shows the number of gallons of gasoline the Beckleys purchased on their road trip. What was the total cost for gasfor the trip? 4.89 x 12= 4.72 x 17= 5.09 x 15= $215.27

Multiplying Decimals by Whole NumbersA bee hummingbird has a mass of 1.8 grams. How many grams are 6 hummingbirds and a 4 gram nest?


Multiplying Decimals by Whole NumbersA bee hummingbird has a mass of 1.8 grams. How many grams are 6 hummingbirds and a 4 gram nest?

1.8 1 decimal place x 6 10.8 1 decimal place + 4 14.8 g

Multiplying Decimals by Whole NumbersSharon buys 14 folders for $0.75 each. How much change will she receive if she pays $15?


Multiplying Decimals by Whole NumbersSharon buys 14 folders for $0.75 each. How much change will she receive if she pays $15?

.75 2 decimal places x 14 300 750 10.50 2 decimal places 15 10.50 = $4.50

Multiplying Decimals by Whole NumbersFind two different ways to find the value of the expression 5.7 x 1.17 x 100 that do not require you to first multiply 5.7 x 1.17.


Multiplying Decimals by Whole NumbersFind two different ways to find the value of the expression 5.7 x 1.17 x 100 that do not require you to first multiply 5.7 x 1.17.

Two possible answers.1.17 x 100 = 117 x 5.4 = 666.95.7 x 100 = 570 x 1.17 = 666.9

Multiplying Decimals by Whole NumbersUse the product of 123 x 47 to find the product of 123 x 0.47. Explain the difference between the two products.


Multiplying Decimals by Whole NumbersUse the product of 123 x 47 to find the product of 123 x 0.47. Explain the difference between the two products. 123 123 x 47 x .47 861 8614920 49205781 57.81

The products are different by a factor of 100. Multiplying Decimals by Whole NumbersYour friend thinks that 1.5 x 8 = 1.20 because you do not count the zero when placing the decimal point. Is your friend correct? Explain.


Multiplying Decimals by Whole NumbersYour friend thinks that 1.5 x 8 = 1.20 because you do not count the zero when placing the decimal point. Is your friend correct? Explain.

No, you need the zero to place the decimal point.But you can unannex the zero after you place the decimal point.

Multiplying Decimals by Whole NumbersAgenda NotesHomework Homework Practice 6.3.3Due Tuesday, Sept 23Must show all work!Test Corrections Due Tomorrow

Mid-Chapter 6.3 Quiz Wednesday, Sept 24

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5 Minute Check Complete in your notebook. Find each sum 1. 4.9 + 3.0 2. 0.796 + 13 Find the difference. 3. 19.86 - 4.94 4. 82 – 67.18