Why is subtracting mixed numbers sometimes more complex than adding them?

Subtraction does not have the commutative property, and you may need to borrow from the whole number when the fraction being subtracted is larger.

Which of the following is the correct first step when subtracting mixed numbers with unlike denominators?

Convert the fractions to have a common denominator.

I can subtract mixed numbers with unlike denominators and express the result in simplest form.

1
When subtracting mixed numbers, it is important to subtract the entire mixed number, including both the whole number and fraction parts.
2
When subtracting mixed numbers in stacked form, if the top fraction is smaller than the bottom fraction, you need to borrow or re-group from the whole number part.
3
The stacked form is useful for subtracting mixed numbers because it helps to organize the problem and remember that both parts of the mixed number are being subtracted.