Natalia wants to share some coffee bean chocolates with her friends. If she gave each friend $18$ pieces of coffee bean chocolates, then there will be a $41$ chocolates in excess. If she gave each friend $23$ pieces of coffee bean chocolates, she would be short of $34$ pieces. If she gave each friend $20$ pieces of coffee bean chocolates, how many pieces of coffee bean chocolates will she be left with? 
Overseas Competition->Knowledge Point->Word Problem Modules->Questions Involving Sum, Difference and Multiples->Problems of Difference and Multiple