Answer: -3/4 (choice C)
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Step-by-step explanation:
Think of a whole cake or pizza. Now slice it into 4 equal pieces. This represents 1 is the same as 4/4.
Adding on another quarter slice gets us 4/4+1/4 = 5/4
In other words, the mixed number 1 & 1/4 is the same as the improper fraction 5/4.
So 1 & 1/4 = 5/4
This then means -1 & 1/4 = -5/4 because we multiply both sides by -1.
Now we'll add on 1/2, which is the same as 2/4, like so
(-1 & 1/4) + 1/2
-(1 & 1/4) + 2/4
-(1 + 1/4) + 2/4
-1 - 1/4 + 2/4
-1 + (-1/4 + 2/4)
-1 + 1/4
-4/4 + 1/4
-3/4
which points us to choice C as our final answer
Notice how if we started at -5/4, and moved to the right 2 tickmarks, we arrive at -3/4. Each tickmark represents 1/4 of a unit, so two of them is 2/4 = 1/2.
Side note: -3/4 converts to the decimal -0.75