Why does my child think √48 = 16√3?
Your child takes a square out of a root without its square root, such as √48 = 16√3 instead of 4√3.
Why children do it
Finding the square factor, 16, is the hard part, so it's natural to write it straight out in front. But it comes out as its square root: √48 = √16 × √3 = 4√3. Squaring the answer back checks it: 4√3 squared is 48.
How to help at home
Ask them to check by squaring their answer: (16√3)² is far more than 48.
The right way
Simplify: √48
- √16 × √316 is the biggest square that goes into 48.
- 4√3√16 is 4.
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