To solve for the missing value in the equation:
___ + 500 + 700 = 1300
First, we can combine the numbers on the left side:
500 + 700 = 1200
Now, substitute this back into the equation:
___ + 1200 = 1300
Next, we can isolate the missing value by subtracting 1200 from both sides:
___ = 1300 - 1200
This simplifies to:
___ = 100
So, the missing value is 100.