Question 943193
A class consists of 12 girls and 18 boys. A president, vice-president and treasurer are chosen based on the number of votes. Find the probability of selecting a president, vice-president and treasurer where all 3 are different boys from the class.
<pre>
To get the numerator of the probability,

1. Choose the president any of the 18 boys.
2. Choose the vice-president any of the remaining 17 boys.
3. Choose the vice-president any of the remaining 16 boys.

Numerator of the probability = 18P3 = 18×17×16

To get the denominator of the probability,

1. Choose the president any of the 30 people.
2. Choose the vice-president any of the remaining 29 people.
3. Choose the vice-president any of the remaining 28 people.

Denominator of the probability = 30P3 = 30×29×28

Answer:  {{{(18P3)/(30P3)}}}{{{""=""}}}{{{4896/24360}}}{{{""=""}}}{{{204/1015}}}

That's about 0.2

Edwin</pre>