Answer:
21 Adults= 7 Children , 35 Adults= 15 children and 56 Adults = 24 Children
Explanation:
In other words, every 7 Adults creates a set of 3 Children
In the case of the 21 Adults, 21 /7 = 3sets of Children. Therefore 3x3 =9 Children.
For 35 adults, 35/7 gives us 5 sets
Therefore 5x3= 15 Children
Finally, 56 adults. 56/7= 8 sets
Therefore 8x3= 24 Children
Hope this helps and goodluck. Feel free to post more questions.