You have a bag with 60 black jelly beans and 240 red ones.
a) If you draw one jelly bean out of the bag, find the probability that it is black.
-------60/300= 1/5
b) If you add 60 black jelly beans to the original bag and draw out a bean, what is the probability that it is black?
-------120/360= 1/3
c) How many black beans do you need to add to the original bag to double the original probability of drawing a black bean?
d) Write an equation that represents the problem in part (c).
I GOT A AND B JUST NEED C AND D PLEASE?(: