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It costs Marci 63 cents to mail a postcard and 89 cents to mail a letter. She sent either a postcard or a letter to each of13 people and spent $10.27. Let x represent thenumber or postcards she wrote, write and solveequation odetermine the number of postcards Marci mailed.

Respuesta :

Let

x -----> the number of postcards she wrote

y -----> the number of letters she wrote

we have that

x+y=13 -------> y=13-x -----> equation 1

and

0.63x+0.89y=10.27 -----> equation 2

substitute equation

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