When finding the missing number in a subtraction equation, it can be helpful to use number bonds to decompose large numbers, so the missing part of the whole number can be more easily identifiedFor example, if we have 325 - ? = 50
Decompose the whole number of 325 to 300 and 25
Decompose 300 to 250 and 50
Add 25 back to 250 (275)
The final number bond is 325 for the whole and 275 and 50 for the parts