How do you find the range of 59,55,64,54,56,72,66,58

Determine the number of girls in a math class with 87 boys if there are 25 girls for every 75 boys

If 1/√5+1/√5+1=p+q√r , find the values of p, q and r

He ! a group of farmers planned to clean 80 acres of wheat per day to finish the work on schedule. right before the work started, they received a new piece of machinery that them clean 10 more acres per day than originally planned. as a result of increased productivity in the last day before the deadline they only had to clean 30 acres. how many acres of wheat did the group of farmers have to clean?