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Tom has a collection of 30 CDs and Nita has a collection of 18 CDs. Tom is adding 1 CD a month to his collection while Nita is adding 5 CDs a month to her collection. Find the number of months after which they will have the same number of CDs. show your work

User Diegogs
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2 Answers

2 votes
30:18,
31:23
32:28
33:33
It will be three months before they have the same amount of CDs
User CommandZ
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5 votes

Answer:

3 months.

Explanation:

Let x represent the number of months.

We have been given that Tom has a collection of 30 CDs and he is adding 1 CD a month to his collection.

So number of CDs in Tom's collection after x months would be:
30+x.

We are also told that Nita has a collection of 18 CDs. Nita is adding 5 CDs a month to her collection. So number of CDs in Nita's collection after x months would be:
18+5x.

To solve for number of months, when both will have same number of CDs, we will equate both expressions as:


18+5x=30+x


18+5x-x=30+x-x


18+4x=30


18-18+4x=30-18


4x=12


(4x)/(4)=(12)/(4)


x=3

Therefore, after 3 months they will have the same number of CDs.

User Chris Van Opstal
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