Answer:
The claim is not true
Step-by-step explanation:
We are given that A local retailer claims that the mean waiting time is less than 8 minutes.
A random sample of 20 waiting times has a mean of 6.3 minutes with a standard deviation of 2.1 minutes.
s = 2.1
n = 20
Since n <30 and population standard deviation is unknown
So,we will use t test
So,
t=-3.62
α = 0.01
Degree of freedom = df=n-1=20-1=19
t calculated < t critical
So, we failed to reject null hypothesis
Hence the claim is not true
Answer:
Step-by-step explanation:
We know i×i=i^2 which has value of -1.
We will multiply numerator and denominator by i so the denominator will no longer contain imaginary part(s).
Also multiplying by i/i does not change the value of the fraction because i/i=1.
Numerator × i gives (-5+i)i=-5i+i^2=-5i-1
=-1-5i.
Denominator × i gives (2i)i=2i^2=-2.
So the simplified version of this fraction given is:
The last simplification come from me multiplying fraction by -1/-1.
15y + 31 = 61
15y = 61 - 31
15y = 30
y = 30 ÷ 15
<u>y = 2</u>
Answer:
the answer is 1200
Step-by-step explanation:
