Helen draws a random circle. She then measures its diameter and circumference.
She gets a circumference, C, of 405 mm correct to 3 significant figures.
She gets a diameter, d, of 130 mm correct to 2 significant figures.
Helen wants to find the value of r using the formula r= f
Calculate the lower bound and upper bound for Helen's value of T.
Give your answers correct to 3 decimal places

Complete the statements about the system of linear equation respresented by the tables the equation respented the left table is

Rectangle leg this 11feet and perimeter of 38feet what is the width of the rectangle in feet

2people are trying different phones to see which one has the better talk time. chatlong has an average of 18 hours with a standard deviation of 2 hours and talk-a-lot has an average of 20 hours with a standard deviation of 3. the two people who tested their phones both got 20 hours of use on their phones. for the z-scores i got 1 for the chatlong company and 0 for talk-a-lot. what is the percentile for each z-score?