🚀 go-pugleaf

In article <3335E89E.71A8@nbnet.nb.ca>, Bill Best <kellyc@nbnet.nb.ca> wrote:

> I am having problems with the following question. Could you please help
> me by showing me how it is worked out. I've been through my textbook and
> my mom has tried to figure it out..maybe I can help you in return in the 
> near future:
> 
> Craig is one year less than twice as old as Colin. The sum of three times 
> Craig's age and twice Colins's age is 45. Find their ages.  The answer is
> Craig is 11 and Colin is 6. Please show me how they figured this out?
> I am knew at word problems..grade 10.

Let x = Colin
Let y = Craig
  
            y = 2x - 1
 3(2x-1) + 2y =45

Sustitute (2x-1) into 3(2x-1) +2y =45

to get    3(2x-1) + 2(2x-1) =  45
          6x -3 + 4x -2     =  45
         10x  -5            =  45
                    10x     = 50
                      x     = 5

substitute x=5 into any of above equations to solve for y
y  = 2*5 -1
    y  =  9

Then Colin is 5 and Craig is 9
Double check.

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Take everything I write with a grain of .........

Guy Desautels
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