A test is worth 100 points containing 38 problems. Each problem is either 2 points or 5 points. How many of each value are there?
f = five point q's
t = two point qs = 38 - f
five point total will be 5f
two point total will be 2 (38-f) summed together = 100 points
5f + 2 (38-f) = 100 solve for f , the number of 5 point q's then the remaining questions, the 2 pointers = 38-f