Square Root: 5 Mistakes to Avoid
Finds the square root. The maths is not complicated, but a handful of errors come up again and again in this and related math & geometry calculations. Here is what to watch for.
Rounding is a common source of small errors. Keep full precision during intermediate steps and round only the final answer to the number of decimal places or significant figures the question asks for.
These calculations appear throughout the Singapore syllabus, from primary school percentages and fractions to secondary school algebra and geometry. Understanding the formula makes problem sums easier because you can recognise which quantity is missing.
1. Confusing radius and diameter
Many circle formulas use the radius, which is half the diameter.
2. Population versus sample formulas
Sample standard deviation divides by n − 1; population divides by n.
3. Dropping negative signs
Signs matter for roots, changes and differences.
4. Forgetting the order of operations
Powers and brackets come before multiplication and addition.
5. Using the wrong percentage base
A percentage change is measured against the original value, not the new one.
The correct method
√x is the number that multiplied by itself gives x.
For example, with these inputs:
- Number: 50
the calculator returns:
- √x: 7.0711
Related calculations
- Perimeter of an Ellipse Calculator: Calculates the perimeter of an ellipse from the measurements you enter.
- Arc Length Calculator: Calculates the arc length from the measurements you enter.
- Volume of a Cube Calculator: Calculates the volume of a cube from the measurements you enter.
- Volume of a Cuboid Calculator: Calculates the volume of a cuboid from the measurements you enter.
The Square Root Calculator applies the formula consistently, so it is a quick way to double-check your own working.
Run your own numbers: Square Root Calculator