Jane weighed 73 pounds and 3 ounces last year. She gained 13 ounces this month.

10 pounds

Step-by-step explanation:

13-3=10 ibs

Explanation:

For now, let's ignore the 73 pounds.

The 13 ounces she gains is added onto the initial 3 ounces to get 3+13 = 16 ounces = 1 pound.

So we add this 1 pound onto the 73 pounds from earlier to get the answer to be 73+1 = 74 pounds

We could write the steps out like this

(73 pounds, 3 ounces) + (13 ounces)

(73 pounds + 3 ounces) + (0 pounds + 13 ounces)

(73 pounds + 0 pounds) + (3 ounces + 13 ounces)

73 pounds + 16 ounces

73 pounds + 1 pound

74 pounds