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CanadaON
Grade 3

EXT: Write mixed operations number sentences

Lesson

When we solve number problems, sometimes we need to solve one part of our problem first, and then the rest. This video shows you how to work through two steps to solve one problem.

 

Worked Examples

Question 1

Gwen collected sticks at the park and laid them on the ground in $2$2 groups with $3$3 sticks in each group.

David also collected sticks and laid them on the ground in $5$5 groups with $5$5 sticks in each group.

Gwen:                
                   
David:        
  1. Which number sentence matches the total number of sticks?

    $2+3\times5+5$2+3×5+5

    A

    $2+3+5+5$2+3+5+5

    B

    $2\times3+5\times5$2×3+5×5

    C

Question 2

The following problem was being solved by Marge and Dave.

$5$5 boxes with $10$10 donuts in each box were delivered to work in the morning. $6$6 donuts were eaten over the course of the day. How many donuts are left altogether?

  1. Who was correct?

    Marge said that $5$5 boxes of $10$10 donuts is $50$50 donuts, and $6$6 less donuts makes $44$44 donuts in total.

    A

    Dave said that $5$5 boxes of $10$10 donuts is $15$15 donuts, and $6$6 less donuts makes $21$21 in total.

    B
  2. Write Marge's correct statement using a number sentence.

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