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How would you divide. 3,180 ÷ 15?. In this lesson you will learn how to divide by using an area model. Multiplication and division are inverse operations. 45 ÷ 9 = n. n x 9 = 45. 9 x n = 45. Challenging problems can be broken into smaller parts. Then I can multiply 26 x 10 and get 260.
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How would you divide 3,180 ÷ 15?
In this lesson you will learn how to divide by using an area model.
Multiplication and division are inverse operations. 45 ÷ 9 = n n x 9 = 45 9 x n = 45
Challenging problems can be broken into smaller parts Then I can multiply 26 x 10 and get 260 20 x 13 I know that 20 is 2 times 10 20 = 2 x 10 I can multiply 13 x 2 and get 26 13 x 2 = 26 26 x 10 = 260 20 x 13 = 260
An area model can be used to show division. length = 6 width = 4 24 24 ÷6 = 4
3,180 ÷ 15 30 divides easily by 15 Smart rounding ≈ 3,000 ÷ 15 Smart estimate ≈200
3,180 3,180 ÷ 15 15 - 3,000 (15 x 200) 15 180 10 x 15= 150 100 x 15= 1,500 200 x 15 = 3,000 - 150 (15 x 10) 30 3,000 200 -(200 x 13) = 2,600 - 30 (15 x 2 ) 0 260 10 x 15= 150 This makes sense since our smart estimate was 200 10 -(20 x 13) =260 150 2 30 2 x 15= 30 0 212 x 15 = 3,180 3,180 ÷ 15 = 212
There are 1,438 stickers for 13 students. How many stickers does each student get? Smart rounding ≈ 1,400 ÷ 14 1,400 divides easily by 14 Smart estimate is around 100
1,438 ÷ 13 1, 438 13 - 1,300 (13 x 100) 13 138 10 x 13= 130 100 x 13= 1,300 - 130 (13 x 10) 8 1,300 100 -(200 x 13) = 2,600 260 10 x 13= 130 This makes sense since our smart estimate was 100 10 -(20 x 13) =260 130 0 8 left 110 x 13 + 8 = 1,438 1,438 ÷ 13 = 110 with 8 left
In this lesson you have learned how to divide by using an area model.
Use an area model to divide 1,845÷ 15. Explain your work. • Rita is sorting her giant penny collection into boxes. She wants each box to have the same number of pennies. She has 2,435 pennies. If she has 12 boxes, how many pennies will she put in each box. Will she have any left over? How much money does she have?
Which model shows the division of 1,420 ÷ 20? 400 800 A B C 800 800 20 20 20 260 260 260 220 400 400 20 220 40 400 40 20 20 -(20 x 13) =260 20 -(20 x 13) =260 11 11 0 1 -(20 x 13) =260 0
Which model shows the division of 2,820 ÷ 12? 1200 1200 A B C 2400 2400 12 12 12 260 260 260 360 360 360 60 120 100 200 200 100 30 -(20 x 13) =260 30 -(20 x 13) =260 10 30 0 5 -(20 x 13) =260 0