Answer:
6 red balls
Step-by-step explanation:
The probability in the first pick
6/21
The probability in the second pick (without replacement)
5/20
the requested probability
(6/21)(5/20) = 30/420
simplification
30/420 = 3/42 = 1/14
Hope this helps
Our answer is
Our greatest common factor, or GCF, is
, so when we factor is out, our divide each term by
, we get our answer. To check this, we can multiply the
back across the parenthesis and see if we get the same result as our initial question.
Hope this helped! :))
Let n = the hours elapsed when the two trains are 660 miles apart.
Let the first train travel east and the second train travel west.
The distance traveled by the first train is
x = (50 mi/h)*(n h) = 50n mi
The distance traveled by the second train is
y = (60 mi/h)*(n h) = 60n h
The distance between the two trains after n hours is
x + y = 50 n + 60n = 110n mi
Because this distance is 660 miles, therefore
110n = 660
n = 6 hours
Answer: 6 hours
I hope this helps. Sorry it took so long
