39 is 40% of what number (please explain)

Bradley completed latex: \frac{3}{5} 3 5 of his homework. what percent of his homework does he still need to complete?

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

For the inequality |c| < |d| to be true, which of the following must be true?