Answer:do it yo self
Step-by-step explanation: get yo daam calculator and do it
Answer: We reject the null hypothesis, and we use Normal distribution for the test.
Step-by-step explanation:
Since we have given that
We claim that
Null hypothesis : 
Alternate hypothesis : 
There is 5% level of significance.

So, the test statistic would be

Since alternate hypothesis is left tailed test.
So, p-value = P(z≤-2.31)=0.0401
And the P-value =0.0401 is less than the given level of significance i.e. 5% 0.05.
So, we reject the null hypothesis, and we use Normal distribution for the test.
Answer:
The mean of the combined group is 76.67 ≈ 77
Step-by-step explanation:
- The sum of the grades in Tom's group is 20×70 = 1400
- The sum of grades in Alice's group is 10×90=900
- The sum of gradees in the combined group is =1400+900=2300
- Then the mean grade of the combined group is

where
- 2300 is the sum of the all grades in the combined group
- 30 is the total number of people in the group
Answer:
x = 1
Step-by-step explanation:
Nine and ninety-eight hundreths