The times of the runners in a marathon are normally distributed, with a mean of 3 hours and 50 minutes and a standard deviation of 30 minutes. what is the probability that a randomly selected runner has a time less than or equal to 3 hours and 20 minutes? use the portion of the standard normal table below to answer the question.
16%
32%
34%
84%

The answer is 16%

Step-by-step explanation:

Given a mean of 3 hours and 50 minutes and a standard deviation of 30 minutes

so a time less than or equal to 3 hours and 20 minutes is a time 1 standard deviation OUTSIDE from the mean

Use the probability table:

The probability that a randomly selected runner has a time less than or equal to 3 hours and 20 minutes

= Probability of z being outside 1 SD from mean

= 1 - Probability of z within 1 SD from mean

= 1 - 0.84

= 0.16 or 16%

not only in mathematics, scientific proof also are required in the other field of science. also maths proofs are of particular structure, containing steps and logics. so proving is like doing science, it is science. that's why it is important to prove. 

an inaccurate proof leads to errors, or stating results that are not accurate.  which wil mess the probelm up you dont want this

4 candies

step-by-step explanation:

7 x 28 = 196

200 - 196 = 4 candies remaining.