Question 479698
{{{P=(18C2*12C2)/(30C4)}}}
{{{18C2=18!/(2!(18-2)!)=18!/(2!*16!)=(16!*17*18)/(2*16!)=153}}}
{{{12C2=12!/(2!(12-2)!)=12!/(2!*10!)=(10!*11*12)/(2*10!)=66}}}
{{{30C4=30!/(4!(30-4)!)=30!/(4!*26!)=(26!*27*28*29*30)/(2*3*4*26!)=27405}}}
{{{P=(18C2*12C2)/(30C4)=(153*66)/27405=0.3685}}}