3/8 = 6/16 after multiplying top and bottom of the original fraction by 2
So the mixed number 19&3/8 is the same as 19&6/16
Subtract off 1/16 to account for the width of the saw
6/16 - 1/16 = 5/16
note how I only worried about the fraction portion. I didn't worry about the whole part 19
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So after accounting for the width of the saw, we have 19&5/16 of metal left over. Now subtract off the value 11&9/16
If you line up the mixed numbers, you'll see that 5/16 is over top 9/16 when we subtract. The top fraction 5/16 is smaller than 9/16, so we have to borrow
Borrow 1 from 19 and that 19 drops to 18. Carry that 1 over to add to 5/16 and we get
1+5/16 = 16/16+5/16 = 21/16
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19&5/16 turns into 18&21/16 which allows us to subtract like so
(18&21/16) - (11&9/16) = (18-11) & (21/16-9/16) = 7&12/16 = 7&3/4
So you will have 7&3/4 inches of metal left over, which is not enough to make another fixture since you need 11&9/16
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Final Answer: Choice A) 7 & 3/4