Tennis great Roger Federer made 63% of his first serves in a recent season. When Federer made his first serve, he won 78% of the points. When Federer missed his first serve and had to serve again, he won only 57% of the points. Suppose you randomly choose a point on which Federer served. You get distracted before seeing his first serve but look up in time to see Federer win the point. What's the probability that he missed his first serve?

Sounds like a Bayes Theorem problem.

Events:

F: Roger makes his first serve.  We'll write ~F for "not F".

P(F) = .63

P(~F) = 1 - .63 = .37

W: Roger wins the point.  We don't know P(W) but we are given

P(W | F) = .78

P(W | ~F) = .57

We're asked for

P(~F | W)

The basic conditional probability theorem is

P(~F and W) = P(~F | W) P(W) = P(W | ~F) P(~F)

P(~F | W) = ( P(W | ~F) P(~F) ) / P(W)

We write

P(W) =  P(W | F) P(F) +  P(W | ~F) P(~F)

Substituting gives Bayes' Theorem:

P(~F | W) = ( P(W | ~F) P(~F) ) / ( P(W | F) P(F) +  P(W | ~F) P(~F) )

We know all the parts so we substitute,

P(~F|W) = ( .57(.37) ) / (.78(.63) + .57(.37) ) = 0.30029901751388294

Let's call that 30%

30%

step-by-step explanation:

in which figure is point g a centroid

the most boring ever written

step-by-step explanation:

i am writing something. yes, i plan to make it the most boring thing ever written. i go to the store. a car is parked. many cars are parked or moving. some are blue. some are tan. they have windows. in the store, there are items for sale. these include such things as soap, detergent, magazines, and lettuce. you can enhance your life with these products. soap can be used for bathing, be it in a bathtub or in a shower. apply the soap to your body and rinse. detergent is used to wash clothes. place your dirty clothes into a washing machine and add some detergent as directed on the box. select the appropriate settings on your washing machine and you should be ready to begin. magazines are stapled reading material made with glossy paper, and they cover a wide variety of topics, ranging from news and politics to business and stock market information. some magazines are concerned with more recreational topics, like sports card collecting or different kinds of hairstyles. lettuce is a vegetable.