Difference between revisions of "2011 CEMC Gauss (Grade 8) Problems/Problem 6"
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Latest revision as of 15:01, 19 October 2025
Problem
If Clara doubles a number and then adds 
, the result is 
. The original number is
Solution 1
Let 
be the original number that Clara chose. Setting up an equation, we get:
Solving for n gives:
~anabel.disher
Solution 2
We can work backwards, and subtract from the final result, and then halve the result to get the original number. This gives:
~anabel.disher
| 2011 CEMC Gauss (Grade 8) (Problems • Answer Key • Resources) | ||
| Preceded by Problem 5 |
Followed by Problem 7 | |
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| CEMC Gauss (Grade 8) | ||
