Mathematics for IGCSE & O level - Estimation (Section 3 - No. 6)
What is the first step in estimating the cost of 24 golf balls at $5.75 each?
Use a calculator to find the exact cost.
Round $5.75 to one significant figure.
Multiply 24 by 5.75 directly.
Add the cost of the golf balls.
Explication
The first step in estimation is to round to one significant figure.