how would you use estimation to find the answer to 2,860 ÷ 13?

How would you use estimation to find the answer

to

2,860 ÷ 13?

In this lesson you will learn how to divide

by estimating and adjusting the quotient.

Let’s ReviewLet’s ReviewMultiplication and division are inverse

operations.

45 ÷ 9 = n

n x 9 = 45

9 x n = 45

Let’s ReviewLet’s ReviewChallenging problems can be broken

into smaller parts20 x 13

20 = 2 x 10

I know that 20 is 2 times 10

I can multiply 13 x 2 and get

26

Then I can multiply 26 x 10

and get 260

26 x 10 = 260

13 x 2 = 26

20 x 13 = 260

Let’s ReviewA Common Mistake

Dividing with very small numbers

1,215 ÷ 10Running total

Quotient

1,215

608

2 -(2x10)=201,196

Let’s ReviewCore Lesson2,860 ÷ 13

Smart rounding ≈ 2,400 ÷ 12

Smart estimate ≈200

24 divides easily by 12

Let’s ReviewCore Lesson2,860 ÷ 13 This

makes sense since our smart estimate was 200

Running total Quotient

2,860

10 x 13= 130100 x 13= 1,300

200 x 13 = 2,600

-(200 x 13) = 2,600

260

20013 x 1= 1313 x 2 = 2613 x 20 = 260

-(20 x 13) =260

0

20

220

Let’s ReviewCore LessonThere are 1,716 stamps for 16 students.

How many stamps does each student get?Smart rounding ≈ 1,600 ÷ 16

Smart estimate ≈100

1,600 divides easily by 16

Let’s ReviewCore Lesson1,716 ÷ 16 This

makes sense since our smart estimate was 100

Running total Quotient

1,716

10 x 16= 160100 x 16= 1,600

-(100 x 16) = 1,600 116100

10 x 16= 160Too large5 x 16 = 80

-(5 x 16) =8036

52 x 16 = 32

-(2 x 16) =32

4 left

2

107

In this lesson you have learned how to divide

by estimating and adjusting the quotient.

Let’s ReviewGuided PracticeUse estimation and adjustment to solve 2,860 ÷ 13. Running total

Quotient

2860

Let’s ReviewExtension ActivitiesUse estimation and adjustment to solve

2,575 ÷ 23. Explain your work.

Susanna is sorting her giant button collection into boxes. She wants each box to have the same number of buttons. She has 3,920 buttons. If she has 15 boxes, how many buttons will she put in each box. Will she have any left over?

Let’s ReviewQuick Quiz

Which table shows how to divide 1,655 ÷ 15?

Running total Quotient

1,655

-(100 x 15)=1500

100

155-(10 x 15) =

150

10

5 left 110 

Running total Quotient

1,655-(9 x

112)=1008112

647-(40 x 15) =

600

40

47 left 152

Running total Quotient

1,655

-(100 x 16)=1600

100

55-(10 x 5) = 50

10

5 left 110 

A B C

Let’s ReviewQuick Quiz

Which table shows how to divide 1,248 ÷ 12?

Running total Quotient

1,248

-(100 x 12)=1,000

100

248-(12 x 20)

=240

10

58 left 110 

Running total Quotient

1,248-(12 x

100)=1,200100

48-(12 x 4) = 48

4

0 104

Running total Quotient

1,248

-(100 x 12)=1,100

100

148-(12 x 12)=

144

10

4 left 110 

A B C