Question 1 :
A researcher studying the behavior of mice has recorded the time (in seconds) taken by each mouse to locate its food by considering 13 different mice as 31, 33, 63, 33, 28, 29, 33, 27, 27, 34, 35, 28, 32. Find the median time that mice spent in searching its food.
Solution :
31, 33, 63, 33, 28, 29, 33, 27, 27, 34, 35, 28, 32
Ascending order of given data is
27, 27, 28, 28, 29, 31, 32, 33, 33, 33, 34, 35, 63
Middle value is 7^{th} observation
Median = 32
Question 2 :
The following are the marks scored by the students in the Summative Assessment exam
Class 0 - 10 10 - 20 20 - 30 30 - 40 40 - 50 50 - 60 |
Number of students 2 7 15 10 11 5 |
Cumulative frequency 2 9 24 34 45 50 (N) |
N/2 = 50/2 = 25^{th} value
Median class = 20 - 30
l = 20, N//2 = 25, m = 9, f = 15 and c = 10
Median = 20 + ([25 - 9]/15) x 10
= 20 + (16/15) x 10
= 20 + 1.06(10)
= 20 + 10.6
= 30.6
Hence the median of the given data is 31.
Question 3 :
The mean of five positive integers is twice their median. If four of the integers are 3, 4, 6, 9 and median is 6, then find the fifth integer.
Solution :
Let "x" be the fifth observation.
Mean of 5 observations = (3 + 4 + 6 + 9 + x)/5
= (22 + x)/5
Median = 6
Mean = 2 median
(22 + x)/5 = 2(6)
22 + x = 12(5)
22 + x = 60
x = 60 - 22
x = 38
Hence the 5th observation is 38.
Kindly mail your feedback to v4formath@gmail.com
We always appreciate your feedback.
©All rights reserved. onlinemath4all.com
Oct 30, 24 10:07 AM
Oct 29, 24 06:24 AM
Oct 29, 24 06:23 AM