Answer:
Step-by-step explanation:
The number is 49, First do 21 / 3 to find what 1/7 of the number is. We get 7, so we know 1/7 is 7 so if we do 7 x 7 we will have 7/7 or one whole and 7x7 is 49. Hope this helps
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 .]
A because I know I’m right because I studied a little bit and I got to get it right
Answer:

Step-by-step explanation:
you have that the average sped is given by the following formula:

The uncertainty formula for a division is given by:
(1)
Δv: uncertainty in speed
Δx: uncertainty in the distance = 0.9m
Δt: uncertainty in time = 0.7s
x: distance = 8.1m
t: time = 1.7s
You replace the values of all parameters in the equation (1):

Hence, the relation between the uncertainty in the average velocity is 0.426
Answer: 1
Step-by-step explanation:
3 copies of 1/3 would be 1/3+1/3+1/3= 1