Answer:
2/9 is the correct option.
Step-by-step explanation:
As the spinner is numbered 2, 4 and 5
The general formula for probability :
P(A) = n(A) / n(S)
n(S) is the number of whole states occur in two spins which is 3 × 3 = 9
n(A) is the event that Rico will get a product of 20.
n(A) = 2 ∵ 4 × 5 and 5 × 4 will bring the product 20.
Therefor, the probability that Rico will get a product of 20 when Rico spins the spinner twice will be:
P(A) = n(A) / n(S)
= 2/9
Therefore, 2/9 is the correct option.
Answer:
V is 60 degree because the v is in the line of 60
•20x200
•4x1000
•8x500
•10x400
•16x250
•2x2000
any of those
Answer: a) 84 and b ) 2084
Step-by-step explanation:
Given : Sample standard deviation : s= $22.82
(Population standard deviation is unknown ) , so we use t-test.
Critical value or the 95% confidence intervals :
Formula to find the sample size :

a) E = 5


i.e. Required sample size : n= 84
b) E = 1


i.e. Required sample size : n= 2084