At the beginning of the school year, there were three 4th grade classes. mr. smith’s class had 19 children, mr. day’s class has 17 children, and ms. brown’s class had 20 children. at the end of the year there were still three classes, but 13 children had moved during the year. how many total students were left at the end of the year?

Tyler went to the supermarket to buy food for a food pantry. he has $36, and can carry up to 20 pounds of food in his backpack. pasta costs $1 for a 1-pound package. pasta sauce costs $3 for a 1.5 pound jar. let x = the number of packages of pasta and y = the number of jars of pasta sauce. one package of pasta is the right amount to go with one jar of pasta sauce. what is the best numbers of packages of pasta and jars of pasta sauce to buy for the food pantry? how many packages of pasta? how many jars of pasta sauce? explain your reasoning.