Warm Up *have work from test moz on desk

Practice – use expanded form and distributive property 17 * 3

9) 23 * 6 Practice – use expanded form and distributive

property 305 * 48

10) 235 * 24

Announcements

• Homework– Testmoz quiz (multiplying decimals – due

Thursday)– Test Corrections – Percents Test (due Friday)– Weekly Math #17 (due Friday)

Remind 101– TO: 704-815-6025– TEXT THIS: @b2615

Vocab Review

• In the equation 4 * 3 = 12, 12 is the _________.• The _________ of 6 are 1,2,3, and 6.• The numbers 18, 27, and 72 are _________ of 9.

Word Bank:Sum multiplesDifference factorsProduct Least Common MultipleQuotient Greatest Common FactorNumerator denominator

Review 5.NBT.1

Practice 1.26 * 10 Which way does the decimalPractice 1.26 ÷ 10 point move?

1) 6.0912 * 10^5 (100000)2) 719.25 ÷ 10^3 (1000)

Review

• Remember Multiplication =

3 * 5 = 5 + 5 + 53 * 0.17 = 0.17 + 0.17 + 0.17

• Remember decimals are like ___________3 * 0.32

Repeated addition

fractions

STRETCH BREAK

Multiplying Decimals with Standard Algorithm

• Step 1 : – Estimate product

• Step 2 :– Stack numbers vertically and multiply (ignore

decimals at first • Step 3: – Insert decimal point into product by:

A – Look back at factorsB – Count total # of decimal placesC – Move product’s decimal point LEFT total # of decimal

places

• Practice : 4.08 * 1.08

1 – Estimate2 – Put both numbers into fraction form

• Why move the decimal point?– Make both numbers into whole numbers

4.08 * 1.08 *

Multiplying Decimals with Standard Algorithm

Practice

• Ben wants to buy a baseball cap that costs $24.50. The state and sales tax is 8% or _____. How much will he pay in sales tax?– 1 : Estimate– 2 : Make both values fractions– 3 : multiply – 4: write as decimal

Rules about multiplying decimals

• 5 * 1.05 = _________ than 1st #

• 5 * 0.05 = _________ than 1st #

• 0.5 * 0.05 = _________ than _______

Warm Up *have work from test moz on desk

Practice – use expanded form and distributive property 305 * 48

11) 66 * 252

12) 304 *10

Announcements

• Homework– Testmoz quiz (multiplying decimals – due

Thursday)– Test Corrections – Percents Test (due Monday)–Weekly Math #17 (due Monday)

Remind 101– TO: 704-815-6025– TEXT THIS: @b2615

Real World with Multiplying Decimals

• Finding cost of groceries and fabric• Area of geometric shapes• Gas and electric bill (171.187 Kwh @ $0.128

per Kwh)

STRETCH BREAK

Review 5.NBT.1

Practice 1.26 * 10 Which way does the decimalPractice 1.26 ÷ 10 point move?

1) 74.1 * 10^4 (__________)2) 381.8 ÷ 10^5 (__________)

Review

• Remember Multiplication =

• Remember decimals are like ___________

Repeated addition

fractions

Multiplying multi-digit decimals

• Four 6th graders are working on a project. They are going to paint a large banner and need to protect the floor. They measured the floor, which is 3.05 meters by 3.658 meters. How many square meters of plastic do they need to cover the entire floor?– 1 : Estimate– 2 : Fractions – What will denominator be?– 3 : Use standard algorithm – how many decimal places?

STRETCH BREAK

Multiplying Decimals with Standard Algorithm

• Step 1 : – Estimate product

• Step 2 :– Stack numbers vertically and multiply (ignore

decimals at first • Step 3: – Insert decimal point into product by:

A – Look back at factorsB – Count total # of decimal placesC – Move product’s decimal point LEFT total # of decimal

places

Practice

1) 0.3 * 0.03 5) 3.04 * 0.62) 1.4 * 0.21 6) 0.66 * 2.523) 0.06 * 1.02 7) 0.2 * 0.94 * 1.34) 12.6 * 2.1 8) 1.54 * 3.05 * 2.6

Practice

1) Madeline studies honeybees. Every week she weighs the same honeybee hive. The first week the hive weighs 11.607 kilograms. Its weight increases about 0.204 kilograms every week. At this rate, how many kilograms will it increase in 7.5 weeks?

2) Your fingernails grow at an average rate of 2.25 inches per year. If they grew at an average rate, you never cut them, and they did not break, how long would your fingernails be in 4.5 years?

Practice

3) The greatest skateboarding speed recorded is 78.37 mph by Roger Hickey in 1990. If he could keep up that speed for 15 minutes, how far could he go?

4) By the age of 21, the best violinists and pianists will have practiced at least 10,000 hours. If you practice an instrument 45 minutes a day for 365.25 days, the length of 1 year, how many hours will you have practiced?

Test Corrections

• Work on Test Corrections and/or Weekly Math #17