MathDB
money of "2"s

Source:

November 17, 2005
probability

Problem Statement

An envelope contains eight bills: 2 2 ones, 2 2 fives, 2 2 tens, and 2 2 twenties. Two bills are drawn at random without replacement. What is the probability that their sum is $20 \$ 20 or more? <spanclass=′latex−bold′>(A)</span> 14<spanclass=′latex−bold′>(B)</span> 27<spanclass=′latex−bold′>(C)</span> 37<spanclass=′latex−bold′>(D)</span> 12<spanclass=′latex−bold′>(E)</span> 23 <span class='latex-bold'>(A)</span>\ \frac {1}{4}\qquad <span class='latex-bold'>(B)</span>\ \frac {2}{7}\qquad <span class='latex-bold'>(C)</span>\ \frac {3}{7}\qquad <span class='latex-bold'>(D)</span>\ \frac {1}{2}\qquad <span class='latex-bold'>(E)</span>\ \frac {2}{3}
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