FUNDAMENTALS OF BUSINESS MATHEMATICS AND STATISTICS I 5.17- Weekly wages of 6 workers are 70, 42, 85, 75, 68, 53 (in `).
Find the G. M. [Ans. 64.209] - Calculate G. M. (upto 2 decimal places) :
(i) 90, 25, 81,^1253 [Ans. 69.08](ii) 125,^7003 , 450, 87 [Ans. 183.90]- Compute G. M. :
(i) 4, 16, 64, 256 [Ans. 32]
(ii) 1, 2, 4, 8, 16 [Ans. 4]
(iii) 2, 79; 0.375, 1000 [Ans. 10.877] - Monthly expenditure of 5 students are as follows :
125, 130, 75, 10, 45, find G.M. [Ans.55.97] - Calculate G.M. of 2574, 475, 75, 5, 0.8, 0.005,, 0.0009. [Ans. 2.882]
- Find G.M. of the table given :
x f
44.5 2
7.05 3
91.72 4
[Ans. 71.38] - Find G.M. of 111, 171, 191, 212, having weight by 3, 2, 4 and 5 respectively. [Ans. 173.4]
- Increase of productions for the first three years are respectively 3%, 4%and 5%. Find average production
of the three years. [Hint : Use G.M] [Ans. 3.9%]
5.1.3. HARMONIC MEAN (H. M.) :
Definition.
The Harmonic Mean (H) for n observations, x 1 , x 2 ,.......x n is the total number divided by the sum of the
reciprocals * of the numbers.
(^1) x
1 2 n
i.e. H n n
(^11) .... (^1).
x x x
= =
- +^
1.^1 x
Again,
H n
=∑ (i.e. reciprocal of H. M = A. M. of reciprocals of the numbers).
- +^
- For ab = 1. a=b^1 , i.e. a reciprocal of b. And fora^1 = b, b is reciprocal of a. Reciprocal of 2 is.^12.