Answer:
Step-by-step explanation:
3pi is irrational because it cannot be expressed as a fraction or decimal. The digits after the decimal point in pi continue on forever without a pattern.
It's too easy just to calculate the actual value:
726 × 5 = 726 × 10/2 = 7260/2 = 3630
_____
You might estimate the value as 700 × 5 = 3500. You might estimate that to be low by 26/700 ≈ 4%, so about 140.
