Sets and Relations
Complex Numbers 33
Sequences and Series
Locus and Straight Line
Measures of Dispersion
Bivariate Frequency Distribution and Chi Square Statistic
Permutations and Combinations
- Introduction of Permutations and Combinations
- Fundamental Principles of Counting
- Concept of Addition Principle
- Concept of Multiplication Principle
- Concept of Factorial Function
- Permutations When All Objects Are Distinct
- Permutations When Repetitions Are Allowed
- Permutations When All Objects Are Not Distinct
- Circular Permutations
- Properties of Permutations
- Properties of Combinations
The mean and S.D. of 200 items are found to be 60 and 20 respectively. At the time of calculation, two items were wrongly taken as 3 and 67 instead of 13 and 17. Find the correct mean and variance.
Compute arithmetic mean and S.D. and C.V.
(Given `sqrt(296)` = 17.20)
|C.I.||45 – 55||55 – 65||65 – 75||75 – 85||85 – 95||95 – 105|
For certain bivariate data, the following information is available.
Obtain the combined standard deviation.
Mean and standard deviation of two distributions of 100 and 150 items are 50, 5 and 40, 6 respectively. Find the mean and standard deviations of all the 250 items taken together.
The mean height of 200 students is 65 inches. The mean heights of boys and girls are 70 inches and 62 inches respectively and the standard deviations are 8 and 10 respectively. Find the number of boys and combined S.D.
The mean and S.D. of a group of 48 observations are 40 and 8 respectively. If two more observations 60 and 65 are added to the set, find the mean and S.D. of 50 items.