Todays typical hip implant weighs about 50% less than it did 20 years ago. if an implant weighs about 3lb today how much did it weigh 20 years ago?

150 is the answer to the problem

If todays hip implant weighed about 50% less then it did 20 years ago, that means that 20 years ago, it weighs 50% more then it does today.

so if it weighs 3 lb today, then 20 years ago it weighed:

3 + 0.5 (3) = 3 + 1.5 = 4.5 lbs <==