Answer:
The probability of picking a black card at random, from a deck with 3 black cards and 7 red ones is 0.3.
Step-by-step explanation:
We will assume that we have 3 black cards and 7 black cards, for a total of 10 cards. Since we are taking one card at random, we can assume that each card is equally likely to be drawn. We have the following event A: The drawn card is a black. We will find the probability of A as counting the number of outcomes that make A to occur and divide it by the total number of possibilities. We are drawing one card, so we have 10 possibilities to be picked. Out of those 10, only 3 cards are black, hence we have 3 possibilites of picking a black card.
Then,
P(A) = 3/10 = 0.3.
So,
Normally a unit rate will be x per 1y. Example: 60 miles/1hr.
Therefore, the option with the denominator as 1 would be the unit rate.
The correct option is C.
Because they are the same equation, just rewritten in a different way.
s = 4p
divide both sides by 4 to get the other equation:
(1/4)s = p