Question

Two more students like math than science

Half the number of students who like science like history.

The number of student who like reading equals the number who like math and science combined.

Two students like History.

How many children (12) like each subject

Answer 1

just put the words into symbols:

m = s+2
h = s/2
r = m+s
h = 2

Now start substituting
since h=2, s=4
since s=4, m=6
now we know that r = 4+6 = 10

Don't know what the (12) at the end means.