Take the mixed number apart and have a whole number and a fraction
1+4 and 5/8 + 7/8
1+4=5
5/8 + 7/8 = 12/8
12/8 = 1 4/8
Add 5 to 1 4/8
5 + 1 4/8 = 6 4/8
1 5/8 + 4 7/8 = 6 4/8
In simplest term, the answer is also 6 1/2
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Another way to solve it is by turning both 1 5/8 and 4 7/8 into improper fractions.
1 5/8 = 13/8
4 7/8 = 39/8
Add them.
13/8 + 39/8 = 52/8
Turn 52/8 into a mixed number.
52/8 = 6 4/8
Simplify it to get 6 1/2.