Answer:
1/2
Step-by-step explanation:
Answer:
Step-by-step explanation:
arc BE is the same as the interior angle, or 76°
BE = 76 °
we can also find arc CE the same way, b/c we can see that the interior angle is the suppment with 76 or 180-76 = CE or 104°
Now we know all the arcs but arc CD
so use the idea that all the way around the circle is 360°
360 = 76 + 104 + 140 + CD
360 - 76 - 104 - 140 = CD
40 = CD
CD = 40 °
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