Question

At a track meet, 50 people ran the 100-meter dash. 2 people finished in 11 seconds, 5 people finished in 12 seconds, 8 people finished in 13 seconds, 10 people finished in 14 seconds, 21 people finished in 15 seconds, 2 people finished in 16 seconds, and 2 people finished in 17 seconds. What is the probability distribution for the finish times?

Answer 1

A probability distribution includes ALL the possible events and must add up to 1. Here you have 50 people, so 50 will be the denominator for each probability ...
P(11 seconds) = 2/50 = 0.04
P(12 seconds) = 5/50 = 0.10
Do this the same for 13, 14, 15, 16 and 17 seconds.
When you are all done, the sum of the 7 probabilities should add up to 1.

Answer 2

P(11 seconds)= 2/50=0.04
P(12 seconds)=5/50=0.10
P(13 seconds)=8/50=0.16
P(14 seconds)=10/50=0.02
P(15 seconds)=21/50=0.42
P(16 seconds)=2/50=0.04
P(17 seconds)=2/50=0.04

Answer 3

is that right?

Answer 4

@YanaSidlinskiy help! =]

Answer 5

Yes. Sometehing like that!!!!:)

Answer 6

im only getting 82 though when i add them up! I Dont understand what Im doing wrong....

Answer 7

I dont understand...

Answer 8

You messed up when you calculated
P(14 seconds)
try that one again and you'll notice it should be .2

Answer 9

Yes, 10/50 = 0.2

Answer 10

OMG thanks soo much =]

Answer 11

You are welcome.

Answer 12

Sorry....I was kind of late...lost connection....Anyways though..I'm glad someone finished helping you:)