What is the unit rate for the ratio 4/7: 8/21?

You put the following items into your rucksack. ham 600 g cheese 380 g tomatoes 270 g how much do all the ingredients weigh in total?

The base of a triangle exceeds the height by 9 inches. if the area is 180 square inches, find the length of the base and the height of the triangle.

The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. according to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?