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Robert had $1.65 in dimes and quarters. The number of dimes he has is 3 more than twice the number of quarters he has. What system of equations could be used to find the number of quarters (q) and dimes (d) that he has?

User Bigballs
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1 Answer

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Final answer:

A system of equations to find the number of quarters (q) and dimes (d) can be set up as: 0.10d + 0.25q = 1.65 and d = 2q + 3. By substituting the second equation into the first, you can solve for q and then find d.

Step-by-step explanation:

To find the number of quarters (q) and dimes (d) Robert has, we can set up a system of equations using the information given:

  1. The total amount of money from dimes and quarters is $1.65.
  2. The number of dimes is 3 more than twice the number of quarters.

These statements can be represented by the following two equations:

  • 0.10d + 0.25q = 1.65 (the value equation representing the total amount of money)
  • d = 2q + 3 (the relationship equation representing the number of dimes in terms of quarters)

Substituting the second equation into the first gives us:

  • 0.10(2q + 3) + 0.25q = 1.65

Then, we can solve for q to find the number of quarters, and afterward, find the number of dimes by plugging the value of q back into the second equation.

User Omer Faruk Ozturk
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