Answer:
NO I HAVE NOT AMAZON ACCOUNT BRAINLIEST
Let r = usual driving rate
let t = usual driving time
We need to figure out t
The distance she covers in her usual time at her usual rate is r*t
The distance she covers in her new time at her new rate is:
(1+t)*((2/3)r)
Set this equal to each other and solve for t.
rt = (2/3)r + (2/3)rt
(1/3)rt = (2/3)r
(1/3)t = (2/3)
t = 2
So her usual time is 2 hours. (There's probably a faster way to do this)
Answer is b hope that helps
Answer:
H0 : σ²= 7.2²
H1 : σ² < 7.2
We can conclude that the mean waiting time of customers vary less, Than 7.2 minutes.
Step-by-step explanation:
H0 : σ²= 7.2²
H1 : σ² < 7.2²
The test statistic :
X² = [(n - 1)*s² ÷ σ²]
s² = 3.5
n = sample size = 25. ; s²
X² = [(25 -1)*3.5² ÷ 7.2²
X² = (24 * 3.5^2) / 7.2^2
X² = 5.67
Pvalue from Chisquare statistic :
P(X² < 5.67) = 0.000042
Pvalue < α ; we reject the Null.
Hence, we can conclude that the mean waiting time of customers vary less, Than 7.2 minutes.