Rich example

# Divide and conquer Add to your resource collection Remove from your resource collection Add notes to this resource View your notes for this resource

## Problem

Without using a calculator, find a reasonable estimate of: $1 \div \sqrt{2}$

What can your thinking about this tell you about other divisions of the form $1 \div \sqrt{n}$?

• Can you select $n$ such that you can write down the value of the division calculation more easily?

• Can you select $n$ such that your answer to the original problem is useful in finding the value of the division?

Without using a calculator, find a reasonable estimate of: $\sqrt{50} \div 10$

Compare this to the original problem: $1 \div \sqrt{2}$.

• What do you notice about your approach?