Answer:
Answer to your query is provided below in the image attached
Answer:75 children
Step-by-step explanation: Let the number of children will be x, so the number of adults will be 215-x
Making equation: 3x+5(215-x)=925
3x+1075-5x=925
-2x=925-1075
-2x=-150
x=75
230.55/8.70 = 26.5 hours (round as appropriate)