I feel like its either b or c
Answer:
30:1
Step-by-step explanation:
45*12 = 540
540/18 = 30
Answer: c. z = 1.35; Reject the null hypothesis
Step-by-step explanation:
Let 
be the average life expectancy of its batteries.
As per given , we have
Null hypothesis : 
Alternative hypothesis : 
Since 
is right-tailed and population standard deviation is also known, so we perform right-tailed z-test.
Test statistic : 
where, n= sample size
= sample mean
= Population mean
=population standard deviation
For 
, we have
Critical one-tailed test value for 0.10 significance level :
Decision : Since critical z value (1.28) < test statistic (1.35), so we reject the null hypothesis .
[When critical value is less than the test statistic value , we reject the null hypothesis .]
Answer:
25,328.941 ÷ 104= 7.90415302
Step-by-step explanation:
Total number of stocks bought = 20
Rate at which each stocks were bought = 31 1/2
= 63/2
Rate at which 20 stocks were bought = 20 * (63/2) dollars
= 10 * 63 dollars
= 630 dollars
Rate at which each stocks were sold = 35 1/4
= 141/4 dollars
Rate at which 20 stocks were sold = 20 * (141/4) dollars
= 5 * 141 dollars
= 705 dollars
Then
Amount of profit made by selling 20 stocks = (705 - 630) dollars
= 75 dollars
So the total amount of profit made is $75. The correct option in regards to the given question is option "D".
