In a survey of 15000 students of different schools, 40% of them were found to have tuition before the see examination. Among them 50% studied only mathematics ,30% only science and 10% studied others subject. how many student studied mathematics as well as science.

600 students.

Step-by-step explanation:

Ok, we start with 15,000 students.

40% of them had tuition, so the actual number of them that had tuition is:

15,000*0.40 = 6,000.

Now we want to find the number of students that studied math and science.

50% only studied math,

30% only studied science

10% studied other subjects.

So 50% + 30% + 10% did NOT studied both math and science

90% is the percentage that did not study math and mathematics as well as science, then the other 10% did.

Then, out of the 6,000 students that had tuition, 10% studied math and science, the total number is:

6,000*0.10 = 600