Answer:
A triangle can be formed.
Value that goes in the box is

It's the same as the first angle mentioned. The value doesn't change.
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Step-by-step explanation:
3/4 = 0.75
1/2 = 0.50
The three given angles in decimal form are:
If these angles add to 180 degrees, then a triangle can be formed.
31.75+53.50+94.75
85.25+94.75
180
So, 31.75+53.50+94.75 = 180 is definitely the case.
Therefore, a triangle can be formed.
You'll type the mixed number
into the box which was that first angle mentioned.