Answer:
9 beads are purple
Step-by-step explanation:
"Of" means "times" in this context, so "3/6 of 18" means (3/6)×18.
3/6 × 18 = (3×18)/6 = 9
9 beads are purple.
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You can probably do this in your head more easily if you realize that 3/6 = 1/2, so the number of purple beads is 1/2 of 18, or 18/2 or 9 beads.