There are several students in the classroom. Some of them have 28 oranges, some have 30 and others have 31. Altogether they have 365 oranges.
How many students are there?
Answer
365=3111+24=2813+1; therefore, there are 12 or 13 students.
But if there are 13 students, they have at least 28*11+30+31=369 oranges.
Therefore, there are 12 students.
