Why does my child think √36 = 18?
Your child halves a number to find its square root, such as √36 = 18.
Why children do it
The square root of 4 is 2, which is also half of 4, so halving can look like the rule. A square root is the number that, multiplied by itself, makes the number: 6 × 6 = 36, so √36 is 6.
How to help at home
Ask them to check by squaring their answer: does 18 × 18 give 36?
The right way
Work out: √36
- 6 × 6 = 36Which number times itself makes 36?
- 6So the square root of 36 is 6.
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