Forty yards of fabric are used to make 9 school baners 40/9

How do you use the elimination method for this question? explain, because i really want to understand!

Which of these numbers of simulations of an event would be most likely to produce results that are closest to those predicted by probability theory? 15, 20, 5, 10

A25- foot ladder leans against a building and reaches a point of 23.5 feet above the ground .find the angle that the ladder makes with the building