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I searched this forum regarding these questions but was unable to find them.
Could anyone PLEASE help me to solve these problems??
#37: The numbers (1,2,3,6) have an average (arithmetic mean) of 3 and a variance of 3.5. What is the average (arithmetic mean) and variance of the set of numbers (3,6,9,18)
answer is 9, 31.5
How do you find variance?
Isn't it
S^2= sum (x-average)^2 / n-1 ?
I don't know how to get 31.5!
#38. Jill has 6 different books. in how many ways can Jill select 2 different books?
answer is 30 but I got 15.
let n=6
let r=2
n!/r!(n-r)! =15...
I dont get it
PLEASE HELP! my exam is next week and I still don't know how to solve these
Could anyone PLEASE help me to solve these problems??
#37: The numbers (1,2,3,6) have an average (arithmetic mean) of 3 and a variance of 3.5. What is the average (arithmetic mean) and variance of the set of numbers (3,6,9,18)
answer is 9, 31.5
How do you find variance?
Isn't it
S^2= sum (x-average)^2 / n-1 ?
I don't know how to get 31.5!
#38. Jill has 6 different books. in how many ways can Jill select 2 different books?
answer is 30 but I got 15.
let n=6
let r=2
n!/r!(n-r)! =15...
I dont get it
PLEASE HELP! my exam is next week and I still don't know how to solve these