Question

I have $25 all in nickels and dimes. There are twice as many Nickles as dimes. How many of each are there?

Answer 1

Answer:

N=250

Step-by-step explanation:

 "twice as many nickels as dimes"     means    N =2D     [eq1]

 "collection of nickels and dimes is worth $25"    means

        5N + 10D = 2500      [eq2]

   (To avoid using decimal points, PLZ express everything in cents.)

Substitution   (substitute N from eq1 into eq2]:

     5(2D) + 10D = 2500

      10D + 10D = 2500

          20D = 2500

            D = 125

      N=2D         [eq1 again]

      N=2(125)

      N=250

Check:

  Is   5(250) + 10(125) = 2500   ?

        1250 +  1250 = 2500   ?

          2500 = 2500   ?yes