word problem

Ayana has 2.35 in nickels and dimes. If she has 33 coins total, find the number of nickels and dimes.    

5N + 10D  =  235         (eq 1)    

  N +     D  =    33         multiply both sides of this by 5    

5N +   5D  =  165         (eq 2)    

subtract (eq 2) from (eq 1)     5N + 10D  =  235    

                                               5N +   5D  =  165    

                                                          5D  =    70    

                                                            D  =    14 dimes    

substitute into original        N + D    =  33    

                                           N + 14  =  33    

                                           N          =  33 – 14    

                                           N          =  19 nickels    

check answer  (5)(19) + (10)(14)  =?  235     

                              95  +  140        =    235 ... luciendo bien    

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