You randomly draw a marble from a bag of marbles that contains 777 blue marbles, 222 green marbles, and 111 red marble. What is
\text{P(not draw a blue marble})P(not draw a blue marble)start text, P, left parenthesis, n, o, t, space, d, r, a, w, space, a, space, b, l, u, e, space, m, a, r, b, l, e, end text, right parenthesis?
Step-by-step explanation: It's quite simple, really. You divide 20 by 4, (the number of pencils and the ratio number) and then you multiply whatever the quotient was by the ratio number for erasers.