Question 782898: Change for a dollar consisted of 15 coins (pennies, nickels, and dimes only) At least one of each type of coin was used. How was this done?
This is one of our challenge questions. I am in Algebra 1 and not sure how to even start trying to solve this. Thank you.
Answer by solver91311(24713)   (Show Source):
You can put this solution on YOUR website!
Let  represent the number of pennies,  represent the number of nickels, and  represent the number of dimes.
First thing we know:
Now since we know that at least one of each is used and that pennies are going to have to show up in groups of 5 so that you come out to an even $1, there has to be at least 5 pennies. But if there were 10 pennies, that would only leave a total of 5 total dimes and nickels -- the most you could have would be 10 + 5 + 40 cents or 55 cents. Therefore, the most pennies you could have is also 5, i.e. there are exactly 5 pennies and a total of 10 nickels and dimes.
So, knowing that we have a total of 10 nickels and dimes and that these 10 nickels and dimes have to add up to 95 cents (one dollar minus the 5 pennies), we can now write:
Solve the 2X2 system for and
John
Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it
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