SOLUTION: This is similar to a question answered by gonzo(654)and was said to be from a textbook. I have tried using the same fomula but cannot get the correct answer. Here is the question

Question 189599: This is similar to a question answered by gonzo(654)and was said to be from a textbook. I have tried using the same fomula but cannot get the correct answer. Here is the question: Sam found a number of nickles, dimes and quarters. He found six more dimes than nickels but three times as many quarters as dimes. The total value of the coins was $11.40. How many coins of each type did Sam find? Can you help?
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
Let n=# of nickels, d=# of dimes, and q=# of quarters

Since "He found six more dimes than nickels but three times as many quarters as dimes", this means that and . We'll call these equations 1 and 2.

Furthermore, because "The total value of the coins was $11.40", this means that

Note: the total value of the nickels alone is (ie the value of ONE nickel multiplied by the number of nickels). The same is applied to the dimes and quarters. These expressions are then added up to get the total value. This is probably where you're stuck.

Start with the last equation.

Multiply EVERY term by 100 to make every number a whole number

Multiply. Let's call this equation 3.

-----------------------------------------------------

So we have the equations

Equation 1:

Equation 2:

Equation 3:

You may see this as a system of equations, which looks like

=========================================================

Start with the third equation

Plug in . Notice how the variable "q" is no longer in the equation.

Multiply

Plug in . Now the variable "d" is gone.

Now we're left with a simple equation with one unknown variable.

Distribute.

Combine like terms on the left side.

Subtract from both sides.

Combine like terms on the right side.

Divide both sides by to isolate .

Reduce.

So this means that there are 7 nickels.

--------------------------------------------

Go back to the first equation

Plug in

Add

So there are 13 dimes

--------------------------------------------

Move onto the second equation

Plug in

Multiply

So there are 39 quarters.

========================================================

Answer:

So there are 7 nickels, 13 dimes and 39 quarters.
RELATED QUESTIONS
There is a question 179241 and answer number 134172. I didn't ask the question but it is (answered by vleith)

I have tried to figure out how this question is answered by using the information from... (answered by Alan3354)

This question has been answered before but I need to be shown the steps in solving by... (answered by rothauserc)

Can I please submit a problem to you by using a word document? I have tried to submit it... (answered by solver91311)

My daughter is doing a summer math packet and we seem to have answered most problems by... (answered by Fombitz)

Shortly after the World Trade Center towers were destroyed by terrorists, America Online (answered by jim_thompson5910)

An equilateral triangle has an area of 300square root of 3. Find the apothem. My... (answered by Earlsdon)

There is this homework problem I have for Pre-Algebra. It is on scale factors. This is... (answered by stanbon)

Gonzo and his friend Duke are heading out to San Diego on a road trip. From Gonzo's front (answered by Alan3354,ikleyn)