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SAI International School
CLASS - X

Mathematics
CHAPTER-14: Statistics

HOME ASSIGNMENT-1

SUBTOPIC : Mean Of Grouped Data

1. Find the mean of the following frequency distribution by direct method.

Class 0 -10 10 - 20 20 - 30 30 -40 40 - 50

Frequency 8 12 10 11 9

Ans:25.2

2. The data of 30 patients attending a hospital in a month are given below. Find the
average number of patients attending the hospital in a day, using assumed mean
method.

Number of patients 0-10 10-20 20-30 30-40 40-50 50-60

Number of days 2 6 9 7 4 2

Ans:28.67

3. Calculate the arithmetic mean of the following frequency distribution using step-
deviation method:
Class Interval 0-80 80-160 160-240 240-320 320-400

Frequency 22 35 44 25 24

Ans:196.8

4. Find the missing frequency, y, if the mean of the data = 49.6
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