77
Subtraction means distance on the number line. From 75 to 100 is 25, and from 100 to 152 is 52. Therefore, 152 - 25 = 25 + 52 = 77. --- Alternately, 150 = 2*75, so 150 - 75 = 75. Add 2 to both sides of that equation, and we get 152 - 75 = 77.