Question 186010
The fractions have to have the same common dominator. So to find that you find the least common multiply. The lcm of 3 and 4 is 12. So your common dominator is 12. Then you multiply 1/3 by 4/4 to get 4/12. Then you mulitply 1/4 by 3/3 to get 3/12. 
So now you have 4/12 +3/12
You add the two numerators and you get 7. 
your answer is 7/12