Subscribe

Grade 3 · Math · Unit 7 of 12

Patterns & Equations

Pattern rules and mystery numbers

What your child practises

Extending increasing and decreasing patterns, describing pattern rules in words and tables, and solving one-step equations like ☐ + 8 = 23.

NWT Curriculum learning standard: Increasing and decreasing patterns; pattern rules using words and numbers; one-step addition and subtraction equations with an unknown number

How we explain it

Children can open this short lesson before they practise.

  1. An equation has an = sign. Both sides are the same.
  2. A letter or box stands for a missing number.
  3. Do the opposite to find it: the opposite of + is −.

Example: n + 7 = 15 Undo + 7 by taking away 7. 15 − 7 = 8. Answer: n = 8

Sample questions

A taste of this unit. In the app, questions change every time and get easier or harder to match your child.

  1. Question 1

    What number goes in the box?

    74 − = 19

    • 93
    • 55
    • 54
    • 56

  2. Question 2

    Follow the pattern. What number goes where the ? is?

    CarsWheels
    14
    28
    312
    416
    5?

    answer box

  3. Question 3

    What number goes in the box?

    48 + = 57

    • 9
    • 10
    • 8
    • 105

  4. Question 4

    What number is missing from the pattern?

    9, 13, , 21, 25

    answer box

  5. Question 5

    Which pattern rule fits?

    225, 200, 175, 150

    • Start at 225 and subtract 50 each time
    • Start at 225 and subtract 25 each time
    • Start at 225 and add 25 each time
    • Start at 200 and subtract 25 each time

  6. Question 6

    Which equation matches the story? The is the number we don't know.

    Sofia had 97 marbles.

    Sofia gave some to friends.

    Now Sofia has 59.

    • 97 − ☐ = 59
    • ☐ − 97 = 59
    • 97 + 59 = ☐

More Grade 3