The blood groups of 200 people is distributed as follows: 50 have type A blood, 65 have B blood type, 70 have O blood type and 15 have type AB blood. If a person from this group is selected at random, what is the probability that this person has O blood type?
Pick one
A) 0.2 B) 0.25 C) 0.3 D) 0.35 E) 0.5
Blood group -	frequency   A - 50   B - 65   O - 70   AB - 15   Let P(E) be the event of getting O blood group   P(E) = Frequency for O blood group / Total frequencies in the above table   = 70 / (65+50+70+15)   = 70 / 200= 
<gadget id="calculator">70 / 200</gadget>
<output>7/20 = around 0.35</output>
0.35   My answer is (0.35)
<result>D</result>
The blood groups of 200 people is distributed as follows: 50 have type A blood, 65 have B blood type, 70 have O blood type and 15 have type AB blood. If a person from this group is selected at random, what is the probability that this person has O blood type?