Helen draws a random circle. She then measures its diameter and circumference.
She gets a circumference, C, of 405mm correct to 3 significant figures.
She gets a diameter, d, of 130mm correct to 2 significant figures.
Helen wants to find the value of π using the formula π=C÷d
Calculate the lower bound and upper bound for Helen's value of π.
Give your answers to 3 decimal places.​