Word problem

Question

My cat Socrates is very furry.

(a) I shaved him two months ago, but I couldn't get all the fur off. The amount of fur he has increased by 15% two months ago, then 35% last month. If he has 5 pounds of fur this month, how much did he have two months ago, right after I shaved him? Round to two decimal places.


____pounds

Answer 1

To get prior month fur weight divide current weight of 5 pounds by 100%+35% or 1.35 = 5 pounds/1.35 = 3.70 pounds prior month weight. Then divide 3.70 by (1+.15) = 3.22 pounds of fur two months ago. 

 

To test the conclusion you can multiply 3.22 pounds by 1.15 to get 3.70 and then 3.70 pounds x 1.35 to get 5 pounds. 

Answer 2

f represents the amount of fur to start

f(1.15) represents the amount of fur two months ago

(f(1.15)(1.35)) represents fur now

 

f(1.15)(1.35) = 5

 

Can you solve for f?