Answer :
1st week - Lost 3 pounds = +3
2nd week - Gained 1 pound = -1
3+13 = + 22
So 22+3 = 25 25-1 = 24
So Tina lost 24 pounds in 13 weeks.
2nd week - Gained 1 pound = -1
3+13 = + 22
So 22+3 = 25 25-1 = 24
So Tina lost 24 pounds in 13 weeks.