Kim made soup which contains 75 total ounces of beans. the soup has two kinds of beans, black and red. there are 4 times as many ounces of black beans as red beans. how many ounces of red beans are in the soup?

Afarmer has a large field that is x feet in length. he wants to fence in a rectangular section in the middle of the field , leaving a length of 100 feet of open field behind each end of the fenced rectangle.he also wants the width of the fenced-in space to be 100 feet less than its length. find the expressions to represent the length and width of the fenced section of the field