SOLUTION: Here is a difficult word problem I am struggling with: 8-year-old Samantha visited Santa at a local department store. He gave her this riddle: " I started working at 15. I

Algebra ->  Customizable Word Problem Solvers  -> Age -> SOLUTION: Here is a difficult word problem I am struggling with: 8-year-old Samantha visited Santa at a local department store. He gave her this riddle: " I started working at 15. I       Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


   



Question 174684: Here is a difficult word problem I am struggling with:
8-year-old Samantha visited Santa at a local department store. He gave her this riddle:
" I started working at 15. I spent 1/4 of my working life in a factory. I spent 1/5 of my working life in an office, and I spent 1/3 of my working life as a school caretaker. For the last 13 years of my working life I've been Santa Claus. How old am I?"
The problem says you need to explain how you got the answer and how you know it is correct.
I am not sure how to explain either of those things! What operations could you do? How do you figure this problem out overall?
Thanks!
-Shelby

Found 2 solutions by Alan3354, stanbon:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
I started working at 15. I spent 1/4 of my working life in a factory. I spent 1/5 of my working life in an office, and I spent 1/3 of my working life as a school caretaker. For the last 13 years of my working life I've been Santa Claus. How old am I?"
--------------------
1/4 + 1/5 + 1/3 = 15/60 + 12/60 + 20/60 = 47/60 of his working life.
The remaining 13/60 must be the 13 yrs as Santa, so that's 60 years.
Add the 15 when he started, and he's 75.
--------------
As a check:
1/4 of 60 = 15
1/5 of 60 = 12
1/2 of 60 = 30
That adds to 47 years. Add 15 and 13, that's 75.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
8-year-old Samantha visited Santa at a local department store. He gave her this riddle:
" I started working at 15. I spent 1/4 of my working life in a factory. I spent 1/5 of my working life in an office, and I spent 1/3 of my working life as a school caretaker. For the last 13 years of my working life I've been Santa Claus. How old am I?"
The problem says you need to explain how you got the answer and how you know it is correct.
-----------------------------
Let "x" be the number of working-life years.
factory time: (1/4)x
office time : (1/5)x
school time : (1/3)x
Santa time : 13 years
-------------------------
Working-life equation: (1/4)x + (1/5)x + (1/3)x + 13 = x
15x + 12x + 20x + 60*13 = 60x
47x + 60*13 = 60x
13x = 60*13
x = 60 (years he worked)
Age = 15 + 60 = 75 yrs. old
===============================
Cheers,
Stan H.