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
Answer:
9 correct
Step-by-step explanation: 60% of 15 = 9
Answer:
84
Step-by-step explanation:
W=cost of one ticket
6w=$4
divide 6 on both sides
w=2/3 dollars per ticket
each child will get two tickets because 6/3 is 2
2/3×2= 4/3= $1.33 per child