Answer:
P(Red card OR four) = 7/13 (0.5385)
Explanation:
A standard deck has 52 cards, half black, half red, four of every number, one from every suit. Probability = no. of desired outcomes/no. total outcomes.
The number of total outcomes is = 52 because there are 52 different cards which can be drawn.
Since the deck of 52 is evenly split between black cards and red cards, the probability of drawing a red card is 26/52, or 1/2 (0.5000).
Since there are 4 cards of each number, the probability of drawing a four, is 4/52, or 1/13 (0.0769).
Since the probability is asking for either (red OR four), the probabilities are added together as either will satisfy the condition, so:
26/52 + 4/52 = 30/52
The final step is to subtract the cards that satisfy both conditions. The two red 4s satisfy both conditions so we must subtract 2/52 from the probability or the cards are counted twice.
30/52 - 2/52 = 28/52 = 7/13
P(Red card OR four) = 7/13 (0.5385)
Hope this helped!