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Work Shown:
5 & 5/8 = 5 + 5/8
-5 & 5/8 = -(5 & 5/8) = -(5 + 5/8) = -5 - 5/8
So,
( -5 & 5/8 ) + ( 3 & 1/2 )
( -5 - 5/8 ) + ( 3 + 4/8 )
( -5+3 ) + ( -5/8+4/8 )
-2 + (-1/8)
-(2 + 1/8)
-(2 & 1/8)
-2 & 1/8
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Alternative Method
We could convert each mixed number to decimal form
-5 & 5/8 = -5-5/8 = -5.625
3 & 1/2 = 3+1/2 = 3.5
( -5 & 5/8 ) + ( 3 & 1/2 ) = -5.625+3.5 = -2.125
Then convert back to mixed number form
-2.125 = -2 & 125/1000
-2.125 = -2 & (1*125)/(8*125)
-2.125 = -2 & 1/8