48.2k views
5 votes
are 7 yellow, 6 blue, 2 red and 3 green ribbons in a drawer. Once a non selected not toplowing probability:n and then a red ribbon)7

User Koby Douek
by
3.6k points

1 Answer

3 votes

Concept

Probability of any event

= number of required outcomes / total number of possible outcomes

Yellow = 7

Blue = 6

Red = 2

Green = 3

Total = 18

Probability of selecting the first ball (green) without replacement

= 3/18 = 1/6

Since the first ribbon is not replaced, the total reduces to 17.

Probability of selecting the second ball (red).

= 2/17

Therefore the probability of selecting green and then red ribbon

' and ' means multiplication


\begin{gathered} \text{ = }(1)/(6)\text{ }*\text{ }(2)/(17) \\ =\text{ }(1)/(3)\text{ }*\text{ }(1)/(17) \\ =\text{ }(1)/(51) \end{gathered}

Final answer

Option C = 1/51

User Alecu
by
3.9k points