<p>A two-sided coin is flipped four times. Given that the coin landed heads up more than twice, what is the probability that it landed heads up all four times?</p>
<p>a)1/16
b)1/6
c)1/5
d)1/4
e)1/2</p>
<p>source: sparknotes practice test #1, 36</p>
<p>The answer is C) 1/5.</p>
<p>Explanation:</p>
<p>The probability of getting a coin that has landed on heads more than twice is:</p>
<ol>
<li>HHHT</li>
<li>HHTH</li>
<li>HHHH</li>
<li>THHH</li>
<li>HTHH</li>
</ol>
<p>We want the probability that it will land on heads all four times (HHHH) so that is 1/5.</p>
<p>This questions looks really confusing lol.</p>
<p>what if this same problem was worded such a way that you couldn’t map out the possibilities?</p>