Answer:
-11
Step-by-step explanation:
Answer:
The fourth term in the sequence is equal to the third term plus the common difference, or 16+3=19- last choice
Answer:
D(3;-2).
Step-by-step explanation:
1) 
2) according to the formulas above:

3) finally, D(3;-2).
Answer: 0.0228
Step-by-step explanation:
Given : The mean and the standard deviation of finish times (in minutes) for this event are respectively as :-

If the distribution of finish times is approximately bell-shaped and symmetric, then it must be normally distributed.
Let X be the random variable that represents the finish times for this event.
z score : 

Now, the probability of runners who finish in under 19 minutes by using standard normal distribution table :-

Hence, the approximate proportion of runners who finish in under 19 minutes = 0.0228