Explanation:
2. The total number of calculators is 6 + 9 + 2 = 17.
When she hands out the first calculator, the probability that it is blue is 2/17.
When she hands out the second calculator, there is one less calculator total, so the probability that it is yellow is 9/16.
The probability of both is therefore:
P = 2/17 × 9/16
P = 9/136
3. There are 13 clubs in a standard deck of 52 cards.
The probability that the first card is clubs is 13/52 = 1/4.
Since you replace the card, there are still 52 cards in the deck. So the probability that the second card is clubs is 13/52 = 1/4.
The probability that both cards are clubs is:
P = 1/4 × 1/4
P = 1/16
4. The total number of pieces of gum is 6 + 9 + 5 = 20.
When you pick the first piece, the probability that it is grape is 6/20.
When you pick the second piece, there's one less piece of gum, and one less grape flavor, so the probability is 5/19.
The probability that both pieces are grape is:
P = 6/20 × 5/19
P = 3/38
5. The total number of drinks is 6 + 3 + 4 = 13.
Since the coach replaces the first drink, the second selection will be independent of the first. So the probability is still P = 6/13.
6. A die has six sides. They are numbered 1 through 6. Three of the numbers are even. Each roll is independent, so the probability of a previous roll does not affect the probability of future rolls.
The probability that you get 3 even numbers, followed by a one, is:
P = (3/6) (3/6) (3/6) (1/6)
P = 1/48