60% of the students finish the test and left. There is 12 students left. How many students are in the class.?

Question

60% of the students finish the test and left. There is 12 students left. How many students are in the class.?

Answer 1

This is easy with direct proportions: 12 students left in the classroom is directly proportional to 40% left in the class room.The total number of students (x which is unknown which we are trying to find) to begin is 100%.

12/x = 40%/100%

40%x = 1200%

x= 30

or

12 is to 40% as x is to 100%:

12/40% = x/100%

40%x = 1200%

x = 30

Therefore, there were originally 30 students to begin with.

Answer 2

x - 0.60x = 12

x (1 - 0.60) = 12

x (0.40) = 12

x = 30

Answer 3

4/10 = 12/x

x = (12  * 10) / 4

= 30 Students

Answer 4

30 students!!

12 students = 40%

6 students = 20%

20% X 5 = 100%  so.... 6 X 5 = 30

Answer 5

40% of the students -> 12 students

100/40 x 12 = 30

There were 30 students in the class.

Answer 6

30

Answer 7

40%<---------->12

20%<----------> 6

100%<--------->30

30 in class