Answer: it will take 23 weeks for both of them to weigh the same.
Step-by-step explanation:
Let x represent the number of weeks that it will take both of them to weigh the same.
Let y represent the weight of Jose in x weeks.
Let z represent the weight of Marty in x weeks.
Jose weighs 180 pounds and plans on gaining 2 pounds per week. This means that
y = 180 + 2x - - - - - - - - 1
Marty weighs 249 pounds and plans on losing 1 pound per week. This means that
z = 249 - x - - - - - - - - 2
To determine the number of weeks that it will take both of them to weigh the same, we will equate both equations. It becomes
180 + 2x = 249 - x
2x + x = 249 - 180
3x = 69
x = 69/3 = 23
