Which is the best estimate for the sum 3/8 and 1/12

When you want to add fractions with different denominators-which are the bottom numbers- you have to find the lowest numbers that you can multiply to go into both numbers.  I know that you can multiply 8×3 to get 24.  And that I can multiply 12×2 to get 24.  So 24 would be what we change the denominators to.  

But we can't just change the denominators.  I have to change the numerators, too.  Since I multiplied 8×3, I have to multiply the numerator by 3, also.  3×3=9.  The new fraction is .  

Do the same thing to the other fraction. But we will multiply by 2. 1×2=2.  So now we have .  We can now add.

+  Only add the top numbers.  We have That fraction cannot be reduced, so  is the final answer.