Answer:
-2/3
Step-by-step explanation:
I find it easier to make these proper fractions into improper fractions.
To make proper to improper, you multiply the denominator with the whole number and then add the product with the numerator.
1 2/3 would become 5/3
2 1/3 would become 7/3
5/3 - 7/3 = -2/3
