Answer:
58°
Step-by-step explanation:
<h3>Angle sum property of triangle:</h3>The sum of all angles of a triangle is 180°.
x + 69 + 55 + x + 78 = 180
x + x + 69 + 55 + 78 = 180
Combine like terms,
2x + 202 = 180
Subtract 202 from both sides,
2x = 180 - 202
2x = -22
Divide both sides by 2,
x = -22/2
x = -11
∠A = x + 69
= -11 + 69
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