10/4 is your answer that is right
1. n=18
2. n=18
3. x=4
4. a= -12
5. x=3
72/9 is equivalent to 8/1
so, option A is your answer.
Answer:
There is no significant evidence to conclude that the mean waiting time is less than 3.8 minutes
Step-by-step explanation:
H0 : μ = 3.8
H1 : μ < 3.8
Test statistic :
(x - μ) ÷ s/sqrt(n)
(3.7 - 3.8) ÷ 0.6/sqrt(60)
Test statistic = - 1.29
The Pvalue from test statistic :
P(z < -1.29) = 0.0985
Reject Null if
Pvalue < α
0.0986 > 0.01 ; Hence, we fail to reject the null ;
There is no significant evidence to conclude that the mean waiting time is less than 3.8 minutes
The formula for volume is base×height×width