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## #1 2018-03-17 13:28:39

Monox D. I-Fly
Member
From: Indonesia
Registered: 2015-12-02
Posts: 1,263

A professional goalkeeper can fend off a penalty kick with the probability of
. In an event a kick is done 5 times. The probability of that goalkeeper being able to fend off those penalty kicks 3 times is ....
A.

B.

C.

D.

E.

Can someone give me a hint?

Actually I never watch Star Wars and not interested in it anyway, but I choose a Yoda card as my avatar in honor of our great friend bobbym who has passed away. May his adventurous soul rest in peace at heaven.

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## #2 2018-03-17 19:34:15

zetafunc
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Registered: 2014-05-21
Posts: 2,200
Website

One way is to use the binomial distribution.

Suppose that
represents the number of times that the goalkeeper saves a penalty. Then,
has a binomial distribution:

You want to calculate
. Do you see why?

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## #3 2018-03-17 21:39:33

Monox D. I-Fly
Member
From: Indonesia
Registered: 2015-12-02
Posts: 1,263

Because what being asked is the probability that the goalkeeper will fend of the kick 3 times?

Actually I never watch Star Wars and not interested in it anyway, but I choose a Yoda card as my avatar in honor of our great friend bobbym who has passed away. May his adventurous soul rest in peace at heaven.

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## #4 2018-03-17 21:41:25

zetafunc
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Registered: 2014-05-21
Posts: 2,200
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Yes -- do you know how to calculate this?

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## #5 2018-03-17 22:23:55

Monox D. I-Fly
Member
From: Indonesia
Registered: 2015-12-02
Posts: 1,263

?

Actually I never watch Star Wars and not interested in it anyway, but I choose a Yoda card as my avatar in honor of our great friend bobbym who has passed away. May his adventurous soul rest in peace at heaven.

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## #6 2018-03-17 22:26:19

zetafunc
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Registered: 2014-05-21
Posts: 2,200
Website

Yes, that is correct.

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## #7 2018-03-17 22:29:03

Monox D. I-Fly
Member
From: Indonesia
Registered: 2015-12-02
Posts: 1,263