A circle has a diameter of 20 centimetres. Taking π as exactly 3.14, enter the number of centimetres in its circumference.

Explication

Multiplying the stated value of π by the full width gives 3.14 times 20 with no other step involved. Entering 125.6 doubles a measurement that already ran the whole way across, and entering 31.4 halves it first even though the rule that uses the width contains no halving at all.