Answer:
The training does reduce response time at 0.05 level of significance
Step-by-step explanation:
Population mean for a population with normal distribution, where the standard deviation is known and the appropriate significant test is given then;
z=x-μ / δ/√n
where
μ= 9 minutes
x=8 minutes
δ= 4.2
n= 36
Applying the formula;
z= 8-9 / 4.2/√36
z= -1 / 4.2/6
z= -1 /0.7 = - 1.429
Perform the test where
H₀ : p=0.05 verse Ha : p < 0.05
Using the Z-table, find the probability that Z is less than -1.43.
You will find the probability of 0.0764 of Z being more than the value in test thus; there are high chances that results will be observed according to the null hypothesis
Since the time difference depends on the initial amount of time, answer #1 is not right
Next, #3 is also not right since the difference is way to great.
Next, #4, we cannot tell how long the workouts of both were, so this is not right either
Therefore, #2 is the right answer
Hope this helped!! :D
0.473684211
Its the answer
Answer:

with 
Step-by-step explanation:
We can study what happens day by day starting with day one (1) to understand how the recursive relation can be constructed:
Day # Number of stamps What is added relative to previous day
1 d1 = 80 + 1 = 81
2 d2 = 81 + 2 = 83 d2 = d1 + 2
3 d3 = 83 + 4 = 87 d3 = d2 + 
4 d4 = 87 + 8 = 95 d4 = d3 + 
5 d5 = 95 + 16 = 111 d5 = d4 + 
6 d6 = 111 + 32 = 143 d6 = d5 + 
(n+1) d(n+1) = dn + 