Answer:
2,200/30=73.3333333
2,300/30=76.6666667
Step-by-step explanation:
Answer:
The condition are
The Null hypothesis is 
The Alternative hypothesis is
The check revealed that
There is sufficient evidence to support the claim that in a small city renowned for its music school, the average child takes at least 5 years of piano lessons
Step-by-step explanation:
From the question we are told that
The population mean is 
The sample size is n = 20
The sample mean is 
The standard deviation is 
The Null hypothesis is 
The Alternative hypothesis is
So i will be making use of
level of significance to test this claim
The critical value of
from the normal distribution table is 
Generally the test statistics is mathematically evaluated as

substituting values


Looking at the value of t and
we see that
so we fail to reject the null hypothesis
This implies that there is sufficient evidence to support the claim that in a small city renowned for its music school, the average child takes at least 5 years of piano lessons.
The variance for the data is 17,507. 5.
Given
The weekly salaries of a sample of employees at the local bank are given in the table below.
Employee Weekly Salary Anja $245 Raz $300 Natalie $325 Mic $465 Paul $100.
<h3>Variance</h3>
Variance is the expected value of the squared variation of a random variable from its mean value, in probability and statistics.
The mean value of the salaries of employees is;

The variance is given by;

Hence, the variance for the data is 17,507. 5.
To know more about variance click the link given below.
brainly.com/question/7635845
$10.50a + $3.75b = $2,071.50
It is given that b = 82
Therefore - $10.50a + ($3.75)(82) = $2,071.50
or $10.50a + $307.50 = $2,071.50
$10.50a = $2,071.50 - $307.50 = $1,764.00
Therefore - a (number of adult tickets sold) = $1,764.00/$10.50 = 168 tickets