A teacher records the test marks of 25 students and calculates the class mean to be 72. Jean-Pierre finds out that his mark of 86 was recorded incorrectly as 36. What will the corrected class’s mean be?

If the altitude is drawn to the hypotenuse of a right triangle, then the two triangles formed are similar to the original triangle and to each other. which set of triangles shows the similar triangles created by the altitude in the diagram?