Let the counts of "ranchers" and "starbursts" be r and s respectively. Then r = (3/5)s.
The total number of pieces of candy is 120, which must equal r + s, or (3/5)s + s.
We multiply both sides of the equation by 5, to eliminate fractions:
600 = 3s + 5s = 8s
Then 8s = 600, and s = 75.
There are 75 pieces of Starburst candies and (3/5)(75), or 45, pieces of Jolly Ranchers candy. Note that 75+45 = 120 total.
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