Question 527205: How many combinations can be made into 41 cents only using pennies, quarters, dimes, and nickles
Answer by Edwin McCravy(20056) (Show Source):
You can put this solution on YOUR website!
31 ways. Here's why:
You can either use no quarter, or 1 quarter.
Case 1: you don't use a quarter.
1. If you don't use any dimes, then you can use from 0 through 8 nickels
and the rest pennies. That's 9 ways.
2. If you use exactly 1 dime, you can use from 0 through 6 nickels
and the rest pennies. That's 7 ways.
3. If you use exactly 2 dimes, you can use from 0 through 4 nickels
and the rest pennies. That's 5 ways.
4. If you use exactly 3 dimes, you can use from 0 through 2 nickels
and the rest pennies. That's 3 ways
5. If you use exactly 4 dimes, you must use just 1 penny.
That's 1 way.
For case 1, where there are no quarters. there are 9+7+5+3+1 or
25 ways.
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Case 2: you use 1 quarter.
Now the problem is to make the remaining 16 cents using dimes,
nickels and pennies. You can either use no dime or 1 dime.
1. If you don't use a dime, you can use from 0 through 3 nickels
and the rest pennies. That's 4 ways.
2. If you use exactly 1 dime, you can use no nickel or 1 nickel.
and the rest pennies. That's 2 ways.
For case 2, where there is 1 quarter. there are 4+2 or 6 ways to
make the remaining 16 cents.
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Final answer: 25+6 or 31 ways.
Edwin
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