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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. Multiplication and division are inverse operations. 45 ÷ 9 = n. n x 9 = 45. 9 x n = 45.
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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.
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
Dividing with very small numbers 1,215 ÷ 10 -(2x10)=20 2 1,196 608
2,860 ÷ 13 24 divides easily by 12 Smart rounding ≈ 2,400 ÷ 12 Smart estimate ≈200
This makes sense since our smart estimate was 200 2,860 ÷ 13 10 x 13= 130 100 x 13= 1,300 200 x 13 = 2,600 -(200 x 13) = 2,600 200 13 x 1= 13 13 x 2 = 26 13 x 20 = 260 260 20 -(20 x 13) =260 0 220
There are 1,716 stamps for 16 students. How many stamps does each student get? Smart rounding ≈ 1,600 ÷ 16 1,600 divides easily by 16 Smart estimate ≈100
This makes sense since our smart estimate was 100 1,716 ÷ 16 10 x 16= 160 100 x 16= 1,600 10 x 16= 160 Too large 5 x 16 = 80 100 -(100 x 16) = 1,600 116 5 -(5 x 16) =80 2 x 16 = 32 36 2 -(2 x 16) =32 4 left 107
In this lesson you have learned how to divide by estimating and adjusting the quotient.
Use 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?