Question 1166538
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<pre>

Let x be the number of months in Spain;

then the number of months in Columbia is (10-x).


From the condition, you have this equation for the total of the learned words


    200*x + 150*(10-x) = 1700   new words.


From the equation


    200x + 1500 - 150x = 1700

     50x               = 1700 - 1500 = 200

       x                             = 200/50 = 4.


<U>ANSWER</U>.  4 months in Spain and (10-x) = 6 months in Columbia.
</pre>

Solved and explained.


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