Question

the time (in seconds) taken by a group of people to walk across a pedestrian crossing is given in the table below. Time (in seconds) 5-10, 10-15, 15-20, 20-25, 25-30, no.of people, 4, 8, 15, 12, 11, calculate the variance and standard deviation of the data ​

Answer 1

Variance = 37.6

Standard dev = 6.06