Two balls are to be pulled from a vase that contains 7 red balls 9 green balls and 2 black balls. After the first ball Is drawn,
1 answer:
Answer:
Step-by-step explanation:
There are a total of 7 + 9 + 2 = 18 balls in the vase, therefore, when not replacing the first ball, there would be 18 · 17 = 306 ways to pull 2 balls. There are 2 ways to choose the first black ball and then 1 way to choose the second black ball so there are 2 · 1 = 2 ways to choose 2 black balls. Therefore, the probability is 2 / 306 = .
You might be interested in
Answer:
a = 20
Step-by-step explanation:
The mean is calculated as
mean =
= =
Then
= 27 ( multiply both sides by 5 to clear the fraction )
115 + a = 135 ( subtract 115 from both sides )
a = 20
Answer:
Step-by-step explanation:
Given:
If there is a coefficient in front of a or
, that means it becomes an exponent.
Simplify the exponent.
When there is addition between two logarithms or natural logarithms, it means they multiply together.