a dance team has 80 dancers. The ratio of seventh-grade dancers to all dancers is 5:16. Find the number of seventh-grade dancers on the team.

25

Step-by-step explanation:

Each of the 16 "ratio units" representing all 80 dancers must stand for ...

(80 dancers) / (16) = 5 dancers

Then 5 "ratio units" representing seventh-grade dancers will stand for ...

5 * 5 dancers = 25 dancers

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Another way to figure this is to write the proportion ...

(seventh-grade dancers) / (all dancers) = 5/16

seventh-grade dancers = (all dancers) * (5/16) = 80*5/16

seventh-grade dancers = 25