Explanation:
since we are adding, this should be pretty easy! So we know that 2 2/4 also equals 2 1/2. So if we add 2 2/4+ 1 3/4 would equal 4 1/4 because 2+3 equals 5, so we would have 1/4 and 2+1 equals 3 plus 1 equals 4. So our would be 4 1/4.
