A bag holds 3 red, 5 blue and 2 green marbles. One marble is taken at random. What is the probability that it is red?
Answer and explanation
Correct answer: B.
- Step 1: There are 3 + 5 + 2 = 10 marbles in total.
- Step 2: P(red) = 3/10.
Answer
.
Why not the others: : the favourable count was divided by the other counts instead of the total. : this is the probability of NOT drawing the colour. : one colour was left out of the total.
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