In order to take a field trip to the science museum, ms. speedi’s students sold scented pencils for $1. in the classroom, rowena tried to put the $1 bills into 2 equal piles and found one left over at the end. when polly tried putting the bills in 3 equal piles, she also ended up with one extra bill. frustrated, they tried 4, 5, and 6 equal piles and each time had $1 left over. finally rowena put all the bills evenly into 7 equal piles, and none were left over.

based on this information, ms. speedi is sure there is enough money for the fieldtrip!

what is the least amount of money they could have raised? show how you know.
it turns out that they raised more than $500. knowing this, what is the least amount of money they could have raised?