Out of 10 students, the favorite drink of seven is coke and the favorite drink of the rest is fanta. One of the students is chosen at random. What is the probability that the favorite drink of the student is: a .Coke, b. Fanta, c. Neither Coke nor Fanta, d. either Coke or Fanta?
Answers
No. of student chose Coke = 7
No. of student chose Fanta = (randomly 3)
Therefore, 1 student left, whats his favorite drink = (unknown = ?)
Find the favorite drink of the left over student (by probability)
= Coke + Fanta = 10
= 7 + 3 = 10
= (no student left)
= (but now we also don't know that how many students likes fanta?)
= Fanta - Coke = 4
= Fanta = 4
= (now 1 student likes both the drinks) (and now we are left with 1 student)
= 1 student = (a) Coke (b) Fanta (c) Neither Fanta nor Coke (d) Either Fanta or coke
= 1 student = Coke
Because if out of ten students one student likes both fanta and coke then its 4 now if the other 1 student which was left can only get coke.. So, the equation is 5-5 on each side..
So, 1 student = Coke
Hope helps YOU