Answer:
A) The best way to picture this problem is with a probability tree, with two steps.
The first branch, the person can choose red or blue, being 2 out of five (2/5) the chances of picking a red marble and 3 out of 5 of picking a blue one.
The probabilities of the second pick depends on the first pick, because it only can choose of what it is left in the urn.
If the first pick was red marble, the probabilities of picking a red marble are 1 out of 4 (what is left of red marble out of the total marble left int the urn) and 3 out of 4 for the blue marble.
If the first pick was the blue marble, there is 2/4 of chances of picking red and 2/4 of picking blue.
B) So a person can have a red marble and a blue marble in two ways:
1) Picking the red first and the blue last
2) Picking the blue first and the red last
C) P(R&B) = 3/5 = 60%
Step-by-step explanation:
C) P(R&B) = P(RB) + P(BR) = (2/5)*(3/4) + (3/5)*(2/4) = 3/10 + 3/10 = 3/5
The common factor in both terms is 10<span />
Answer:
19
Step-by-step explanation:
16+3=19 the key word total means you add
Answer:
2.
30-7x4 = 2
3.
80
Step-by-step explanation:
2.
First, do 7x4, which equals 28. Then subtract that from 30, and you get 2.
3.
Do the parentheses first, 21-6=15. Then 15 divided by 0.2 = 75. 75+5=80.
Sorry I couldn't help on any of the other ones, I don't have much time.
