SOLUTION: Can you help me with this word problem? Dave has a collection of nickles and dimes that is worth $6.05. If the number of dimes was doubled and the number of nickels was decreas

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Can you help me with this word problem? Dave has a collection of nickles and dimes that is worth $6.05. If the number of dimes was doubled and the number of nickels was decreas      Log On


   

Question 203550: Can you help me with this word problem?
Dave has a collection of nickles and dimes that is worth $6.05. If the number of dimes was doubled and the number of nickels was decreases by 10, the value of the coins would be $9.85. How many dimes and nickles does he have?
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
n(.05) + d(.10) = 6.05 ___ 5n + 10d = 605 ___ 5n = 605 - 10d

(n - 10)(.05) + 2d(.10) = 9.85 ___ 5n - 50 + 20d = 985

substituting ___ 605 - 10d - 50 + 20d = 985 ___ 10d = 430 ___ d = 43

substituting ___ 5n = 605 - 430 ___ 5n = 175 ___ n = 35