Question

5.Jasmine has ten cards each showing a number. Half of the cards are red. The probability of selecting a card numbered with a 3 on it is 2/10 or 1/5. There is one card that is both a red and a three card. If Jasmine randomly selects a card, what is the probability that it is either a red or three card?​

Answer 1

Answer: 3 / 5

Explanation:

Given the following :

Number of cards = 10

Half of the cards are red :

Number of red cards = 10 /2 = 5 cards

P(card numbered 3) = 2 /10

Number of Cards that is both red and numbered 3 = 1

Number of cards numbered 3 :

Probability = required outcome / Total possible outcomes

P(card numbered 3) = required outcome / Total possible outcomes

1/5 = required outcome / 10

Required outcome = (1/5) × 10 = 2 cards

Probability that card is either red or numbered 3:

Number of red cards and not numbered 3 = 5 - 1 = 4

Number of cards number three and not red = 2 - 1 = 1

Number of cards numbered 3 and red = 1

= (4 + 1 + 1) = 6 cards

P(either red or numbered 3):

= 6 / 10

= 3 / 5