Answer:
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
35 students would not know any of the three languages, because if 30 know French, 19 knew German, and 16 knew Russian, that must mean that 65 students know at least one of the three languages. So you subtract 65 from 100 and end up with 35
Luis is finding 5 because 9 minus 6 is 3. 3 plus 2 equal 5 easy