Answer:
a) You have a 30% of not drawing yellow or green
b) You'd have a 46% of frawing a red or green bead
Explanation:
Total beads: 42 + 28 + 12 + 18 = 100
Green beads + yellow beads = 28 + 42 = 70
100 - 70 = 30
30/100 = 0.3 or 30%
Red beads + green beads = 18 + 28 = 46
46/100 = 0.46 or 46%