a certain goal keeper has saved 25% of the penalty kicks she has faced. use the info to calaculate what the probabilty will be that she will save atleast 4 of the next 6 penalty kicks. round answer to the nearest thousandth.

Question

matt101 · Answer

She has a 0.25 chance of saving a penalty kick, so she has 1 - 0.25 = 0.75 chance of not saving a kick. The probability she saves AT LEAST 4/6 kicks is the probability she saves 4/6 kicks or 5/6 kicks or 6/6 kicks

Probability of saving 4/6 kicks:$$(0.25)^4(0.75)^2$$
Probability of saving 5/6 kicks:$$(0.25)^5(0.75)$$
Probability of saving 6/6 kicks:$$(0.25)^6$$

Probability of saving AT LEAST 4/6 kicks:$$(0.25)^4(0.75)^2+(0.25)^5(0.75)+(0.25)^6$$

anonymous · Answer

oh and  can u aswr another question of mine

zarkon · Answer

the are missing something from your answer

matt101 · Answer

Missing what? I didn't work it out and round to the nearest thousandth if that's what you mean...but I assumed gr12 could do it

zarkon · Answer

$${n\choose k}$$

anonymous · Answer

find the probabilty of   P( z> -1.690 to 4 decimal places.

zarkon · Answer

you are missing your binomial coefficients

anonymous · Answer

what is missing?

anonymous · Answer

can u type out a correct solution

matt101 · Answer

That's true haha haven't done this in a while...but using factorial notation should give you the same answer

anonymous · Answer

can u show me?

anonymous · Answer

and can u answr the question i send u above?

matt101 · Answer

I'm assuming you're referring to a normal distribution...For this you'd have to consult a table of z values. Find the probability corresponding to z = -1.69. However, note that the table gives you the area under the curve (the probability) that is LESS THAN your critical value (i.e. z < -1.69). Therefore whatever that number is, subtract it from 1 to get the probability of z being greater than -1.69.

anonymous · Answer

and the question abt the goal keeper is the final answer correct?

matt101 · Answer

My answer should give you the right number. However Zarkon might be able to give you the answer in terms of factorials, which may be what you learned. I don't remember how to do it...been a while since I took statistics...

zarkon · Answer

it will not give the correct answer.  I already told you what you are missing from your solution.

matt101 · Answer

Alright then maybe you could give the solution? I'm down to learn something too :)