Time (in minutes) spent per day on a study app by 40 users of a Kochi college: 15-30: 6, 30-45: 8, 45-60: 12, 60-75: 10, 75-90: 4. The class width here is an awkward 15. Using the step-deviation method with a = 52.5 and h = 15, find the mean time.

Question

Accepted Answer

51.75. Class marks 22.5, 37.5, 52.5, 67.5, 82.5 give u_i = -2, -1, 0, 1, 2 . f_i u_i = -12 - 8 + 0 + 10 + 8 = -2 , f_i = 40 . Mean = 52.5 + 15 (-2/40 ) = 52.5 - 0.75 = 51.75 minutes. "52.45" drops the factor h; "53.25" reverses the sign of u_i ; "46.5" divides by 5, the number of classes, instead of by f_i = 40 .

Time (in minutes) spent per day on a study app by 40 users of a Kochi college:
15-30: 6, 30-45: 8, 45-60: 12, 60-75: 10, 75-90: 4.
The class width here is an awkward 15. Using the step-deviation method with a = 52.5 and h = 15, find the mean time.

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More Class 10 Mean of Grouped Data practice

Time (in minutes) spent per day on a study app by 40 users of a Kochi college:15-30: 6, 30-45: 8, 45-60: 12, 60-75: 10, 75-90: 4.The class width here is an awkward 15. Using the step-deviation method with a = 52.5 and h = 15, find the mean time.

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 10 Mean of Grouped Data practice

Time (in minutes) spent per day on a study app by 40 users of a Kochi college:
15-30: 6, 30-45: 8, 45-60: 12, 60-75: 10, 75-90: 4.
The class width here is an awkward 15. Using the step-deviation method with a = 52.5 and h = 15, find the mean time.