7times what divided by 12 equals 4.2

The equation you need is 7x/12 = 4.2

the first thing you do is multiply 4.2 x 12 (which equals 50.4) to get 7x by itself.
Then you are left with 7x = 50.4 
then you need to divide 50.4 by 7 (so 50.4/7) 
what does that equal?
it equal 7.2 
so x = 7.2