Question: Out of the 150 students, 60% are girls and the rest are boys. Only 1/3 of the boys joined varsity clubs. How many of the boys did not join varsity clubs? Think carefully first, then make a decision:
Out of the 150 students, 100% - 60% = 40% are boys. So, there are 150 x 40 / 100 = 60 boys. Out of the 60 boys, 60 x 1 / 3 = 20 joined varsity clubs. Therefore, 60 - 20 = 40 boys did not join varsity clubs. So the answer is 40.