Step-by-step explanation:
You said the other one would be the last haha just kidding I'm glad to help.
16. 
First, get rid of that parenthesis.

Now multiply both sides by 2 so that you can isolate k


19. 
This is a pretty easy one. If you didn't know, 121/11 is actually 11 :)

Simply multiply by 3 to isolate r :)


Answer:
total marbles;12
after drawing red total counts are 7 red and 4 white 11 in total
probabilities are 4/11
Answer:
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Step-by-step explanation:
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The graph is shown in the attached image.
It would be f= 1.25n+6.25/n