The art teacher needed 100 sheets each of blue paper, red paper, and green paper. She found paper on sale in one-color packages of 50 sheets for $0.99 and multi-color packages of 225 for $2.99 in the following combinations:
Pgk.1:red,blue,yellow
Pgk.2:black,green,red
Pgk.3:green,orange,white
what is the cheapest way to buy the right amount of paper?​