True. The only area where a line parallel to one side would be able to intersect both other sides would be in a place that proportionally divides the other sides.
'A line parallel to one side of a triangle and intersecting the other two sides, divides the other two sides proportionally'.
We see that the given statement is the 'Triangle Proportionality Theorem'.
i.e. Triangle Proportionality Theorem - 'If a line is parallel to one side of a triangle and intersects the other two sides, then it divides the other two sides proportionally'.
First you multiply 8 and 4 to get 32 and that shows you how many campers have agreed to help. Next you have to subtract 32 from 100 to know how many more people you need.