Is this equation correct for this question?

Question

Is the equation  2n-10=48 correct for the following question?

 

Gary decided to make changes to his collection of CDs. He gives away 5 CDs to his friends. Then he buys more to double the number of remaining CDs. He now has 48. 

 

Thanks for helping 

Answer 1

Well Kevin, let us see.

 

 

Let n = the number of CDs he originally had

 

To find the equation, we must work backwards and approach this logically.  He now has 48 CDs.  Before this, he had 24 CDs.  This is how much he had after he gave away 5 CDs.  Add 5 to this amount.  He had 29 CDs originally.

 

 

Using this breakdown, we can come up with an equation.

 

2n - 10 = 48

 

To check the equation, we plug in n=29.

 

2(29) - 10 = 48

58 - 10 = 48

   48 = 48

 

 

You are correct with the equation.

Answer 2

If n=initial number of CD's in Gary's collection, then

   (n-5) is the number he has after giving away 5.

And 2(n-5) is double the number of remaining CD's.

2(n-5)=48   is now many he now has.

This is 2n-10=48.   You got it!