SOLUTION: Hi! I need some help with this word problem. I'm trying to help my 3rd grade son figure out a problem he got wrong on a math test. I know it's simple. I know the answer, but I do

Algebra ->  Expressions -> SOLUTION: Hi! I need some help with this word problem. I'm trying to help my 3rd grade son figure out a problem he got wrong on a math test. I know it's simple. I know the answer, but I do      Log On


   

Question 53591: Hi! I need some help with this word problem. I'm trying to help my 3rd grade son figure out a problem he got wrong on a math test. I know it's simple. I know the answer, but I don't know how to write it out Please help:
Lauren has collected 150 nickels and dimes. She has 70 more nickels than dimes. How many of each does she have?
I came up with 110 nickels and 40 dimes.
Thank you for your time!
Found 2 solutions by checkley71, funmath:
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
YOUR PROBLEM SAYS 50 NICKELS & DIMES. I BELIEVE YOU MEAN 150 NOT 50.
150=N+D & N=D+70 OR SUBSTITUTING (D+70) FOR N WE GET 150=(D+70)+D OR
150=D+70+D OR 2D=150-70 OR 2D=80 OR D=80/2 OR D=40 THEN 150=N+40 OR N=150-40 OR N=110

Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
From the answer you came up with, I think you meant that there was 150 nickles and dimes not 50. So I changed your question, if I'm wrong let me know.
This is a pretty tough question for a third grader. Your son must be pretty smart.
Let the number of dimes=x
Let the number of nickels=x+70
If we add the nickels and dimes together=150
Your problem to solve is:
x+x+70=150
(1+1)x+70=150
2x+70=150
2x+70-70=150-70
2x=80
2x/2=80/2
x=40
The number of dimes=x=40
The number of nickles=x+70=40+70=110