Answer:
3 3/8
Explanation:
We assume your intended question is ...
"Find the actual sum of 1 3/4 + 1 5/8 to determine how much David grew in two years. Explain ..." (Proper word choice and punctuation help communication.)
The sum of the two given mixed numbers can be found several ways. One way is to write the fractions using a common denominator:
1 3/4 + 1 5/8 = 1 6/8 + 1 5/8 = (1 +1) +(6/8 +5/8) = 2 + 11/8 = 3 3/8
David grew 3 3/8 in two years.
__
Both numbers are near and slightly more than 1.5, so their sum will be near and slightly more than 3.