Hello everyone. I"m just wondering why they solved the answer in this manner.(adsbygoogle = window.adsbygoogle || []).push({});

The question is:

A coin is tossed 4 times. Each time the result H for heads or T for tails is recorded. An outcome of HHTT means that heads were obtained on the first 2 tosses and tails on the second 2. Assume heads and tails are equally like on each toss.

Well they solved it this way:

There are 4 outcomes in which exactly one head can occur (since a string of one "T" and three "H"'s can have

the "T" in any one of the string's four positions). So the probability of exactly one head is 4/2^4 = 1/4.

Okay I understand that there are 2^4 possible outcomes on 4 tosses, 2 chocies can happen, either a H or a T, so 2^4.

But Why did they say, since a string of one "T" and 3 "H"'s. If we are trying to find how many times you get exactly 1headWhy wouldn't they say the following:

since a string of one "H" and three "T"s can have the "H" in any one of the strings for positions, such as HTTT, THTT, TTHT, TTTH, this shows its 4 ways, in which you will get exactly 1 head. I'm just confused on why they worded it that way or am I missing somthing?

Thanks

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# Homework Help: Simple coin tossing question, confused on their answer

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