Both answer is 2/51. So answer is C

5/17 * 4/16 * 8/15 hence C

Answer: C
5 red, 4 blue and 8 orange
Selects three randomly

A: P(r and b and o) = 5/17 * 4/16 * 8/15
In first picking, there are 5 red out of 17, thus the probability of taking a red one is 5/17
In second picking, there are 16 ones remaining, out of which there are 4 blue ones, thus the probability of taking a blue one is 4/16
In third Picking, there are 15 ones remaining, out of which there are 8 orange ones, thus the probability of taking an orange one is 8/15

B: P(r and r and o) = 5/17* 4/16 * 8/15
A and ‌B are equal

Quick way of thinking about this problem:

Since we're drawing from the same options, the denominator is not relevant. Now we only have to count how many options we have for each draw. Cross out orange from both sides since it's the same color and comes at the same point in the sequence (3), same thing for red (1), now we only have position (2) to compare. blue vs. red. 4 options for blue, and (5-1) options for red.

They're the same. C.

The question doesn't say without replacement. Why does the solution assume that?

given :- 5Red , 4 Blue , 8 Orange , 3 Other = Total - 20

now
A) P(R∩B∩O) = 5/20*4/20*8/20 = 1/5

B) P(R1∩R2∩O) = 5/20*4/20*8/20 = 1/5

C Answer

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