414 people used public pool. Daily prices are $1.75 for children and $2.00 for adults. Total cost was $755.25. How many adults and children used the pool

Let the number of children who used the pool be c, and the number of adults who used the pool be a. We're given two equations:

a + c = 414

2a + 1.75c = 755.25

We have a simultaneous equations. You can solve this any of 3 ways below: