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Question
Set up and solve a system of equations to solve the problem.
A jar contains n nickels and d dimes. There are 20 coins in the jar, and the total value of
the coins is $1.30. How many nickels and how many dimes are in the jar?
The jar contains
nickels and
dimes.

Respuesta :

sqdancefan

9514 1404 393

Answer:

  • 14 nickels
  • 6 dimes

Step-by-step explanation:

The system of equations can be written ...

  n + d = 20 . . . . . . . . coins in the jar

  5n +10d = 130 . . . . . value in cents

_____

Using the first equation, we can write an expression for n:

  n = 20 -d

We can substitute this into the second equation:

  5(20 -d) +10d = 130

  100 +5d = 130 . . . . . . simplify

  5d = 30 . . . . . . . . . . . . subtract 100

  d = 6 . . . . . . . . . . . . divide by 5

  n = 20-d = 14

The jar contains 14 nickels and 6 dimes.

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