Question 1172477
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In a high school graduating class of 100 students, 54 studied mathematics, 69 studied biology and 35 studied 
both mathematics and biology. If one of these students is selected at random, find the probability that the student:


<pre>
i. Took Mathematics or Biology               54 + 69 - 35 = 88 studied both subjects;
                                             THEREFORE, the probability  P = {{{88/100}}} = 0.88.    <U>ANSWER</U>



ii. Did not take either of these subject     100 - 88 = 12 did not study any of the two subjects.

                                             THEREFORE, the probability  P = {{{12/100}}} = 0.12.    <U>ANSWER</U>


iii. Took Biology but not Mathematics        69 - 35 = 34 studied B but not M. THEREFORE, the probability  P = {{{34/100}}} = 0.34.    <U>ANSWER</U>
</pre>

Solved.  &nbsp;&nbsp;&nbsp;&nbsp;//  &nbsp;&nbsp;&nbsp;&nbsp;All questions are answered.


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To better understand my calculations, see the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/misc/Counting-elements-in-sub-sets-of-a-given-finite-set.lesson>Counting elements in sub-sets of a given finite set</A>

in this site.