Question

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?

Answer 1

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 <==

Answer 2

150 is the answer to the problem