Sometimes in order to solve one problem
you may have to solve "mini-problems" first!

Examples:

Problem A

Josie knows she has lost some money from her pocket.
She had 56¢ and 4 coins, but now has:

Is Josie correct to think she has lost some money?
If so, how much has she lost?

Solution A

Josie is correct in thinking she has lost some money.
She has 2 quarters and 1 penny = 51¢.
Josie had 56¢ to start.
The difference (56-51) would be 5¢.
The fourth coin would be a nickel.

Problem B

Samantha has 4 CDs. 
Samantha and Nicole have 7 CDs together.
Nicole and Rachel have 9 CDs together.
How many CDs does Rachel have? 
 
a)  5             b)  6
          c)  7             d)  8          

Solution B

If Samantha has 4 CDs, 
then Nicole would have to have 3 CDs because 4+3=7.
And
If Nicole has 3 CDs,
Rachel must have 6 because 3+6=9.

Remember:       

Solving "mini-problems" within a larger problem 
can help you solve the larger problems.      

Let's Practice!
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