There are 20 students in a class. Only one-fourth of the students stayed in the classroom while the rest went to the playground. Of those who went to the playground, one-third are boys. How many girls are there on the playground from this class?
Thoughts? Step-by-step reasoning:
Out of the 20 students, 20 x 1 / 4 = 5 students stayed in the classroom. While 20 - 5 = 15 students went to the playground. Out of these 15 students, 15 x 1 / 3 = 5 are boys. Therefore, 15 - 5 = 10 girl students from this class are in the playground.
Thus, the answer is 10.