(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Chp 18, Rev Ex 4

A coin is tossed 25 times. Estimate the chance of getting 12 heads and 13 tails.

Chp 16, Rev Ex 8

A gambler will play roulette 50 times, betting a dollar on four joining numbers each. If one of these four numbers comes up, she gets the dollar back, together with winnings of $8. If any other number comes up, she loses the dollar. So this bet pays 8 to 1, and there are 4 chances in 38 of winning. Her net gain in 50 plays is like the sum of ____ draws from the box ____. Fill in the blanks; explain.

2. Relevant equations

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3. The attempt at a solution

I know how to calculate the expected value and standard error, but that can't possibly be what I use to predict an exact number such as "12 heads." Where am I supposed to go with this one? I could always just brute force it.

On the second, problem I'm confused about the phrasing "8 to 1." Does that mean she bets a dollar and has a chance of getting $9 back? If you said a bet was "2 to 1," I'd assume that meant "either you get $2 back or lose $1"; but you really wouldn't be getting $2 back because you paid a dollar to begin with. See my confusion?

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# Homework Help: 2 quick Stats questions

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