Two cards are drawn from a pack of 52 cards . the probability that either both are red or both are kings ,is
Select
A) 85/528 B) 78/587 C) 55/221 D) 85/25 E) 78/54
clearly n(S)=52C2=(52*51)/2= 
<gadget id="calculator">(52*51)/2</gadget>
<output>1_326</output>
1326   let E1=event of getting both red cards,   let E2=event of getting both kings.   then E1nE2= event getting 2 kings of red cards.   n(E1)=2655/2212=(26*25)/2*1= 
<gadget id="calculator">(26*25)/2*1</gadget>
<output>325</output>
325   n(E2)=455/2212=(12)/2= 
<gadget id="calculator">(12)/2</gadget>
<output>6</output>
6   n(E1nE2)=255/2212=1   p(E1)=n(E1)/n(S)=325/1326   p(E2) =n(E1)/n(S)=6/1326   p(E1nE2)=1/1326   p (both red or both kings=p(E1UE2)   p(E1)+p(E2)-p(E1nE2)   325/1326+6/1326-1/1326=330/1326   =55/221   Answer (55/221)
<result>C</result>
Two cards are drawn from a pack of 52 cards . the probability that either both are red or both are kings ,is