Pierre has 11 coins that equal $0.82. What are the coins?

Answer 1

Well, 2 must be pennies, so that leaves 9 coins to equal 80 cents...

Peace!

Answer 2

Assuming we're using US currency, all the coins except for pennies are in multiples of 5 cents. Since the number of cents ends in 2, then there must be at least 2 pennies. So now we need to find 9 coins that add up to 80 cents.

Now to exhaust all possibilities, start with the highest number of coins you can have in the highest denomination, and keep repeating as you go down to each type of coin. Start with the biggest coin, which is the half-dollar. There can either be one half dollar or no half dollars. If there is one, then we need 8 more coins that add up to 30 cents. There can't be a quarter, because no 7 coins can add up to 5 cents. So move on to dimes. We can't have 3 or more dimes. If there are 2 dimes, we'd need 6 more coins to add up to 10 cents, which can only be one nickel and five pennies. So that's one answer: 1 half-dollar, 2 dimes, 1 nickel, and 7 pennies.

If we continue checking scenarios where there's one half-dollar and either 1 or zero dimes, we'll find that there aren't any other combinations that works. So now move on to where we have NO half-dollars. Then 9 coins must add up to 80 cents. If there are 3 quarters, then 6 coins must add up to 5 cents, which we can't have. If there are 2 quarters, then 7 coins must add up to 30 cents. You'll find there are no possibilities with this set-up. If there is 1 quarter, then 8 coins must add up to 55 cents. You'll find through the same search that there are no possibilities here either.

Finally, let's look at the situation where we have only dimes, nickels, and pennies. 9 of these must add up to 80 cents. We can't have 8 dimes, but 7 dimes and 2 nickels work. This gives a second answer of: 7 dimes, 2 nickels, 2 pennies.

We've got 2 answers, so just finish off the other possibilities to make sure there are no more combinations. 80 cents is a factor of 5, so if there are any pennies in the 9 cents, there have to be 5 of them. But this would give 4 coins adding up to 75 cents, which we can't do with dimes and nickels. So finally, we have to see if there's a combination of just 9 dimes and nickels (but no more than 6 dimes) that gives 80 cents. There has to be an even number of nickels at this point, but 5 dimes and 4 nickels, is below 80s cents. Any lower amount of dimes and more nickels will just give us a lower number.

Answer 3

Start with the lowest amount coins. In this case, pennies.

2 pennies + 1 nickel + 3 quarters = 6 coins

Now start breaking up the higher amount coins - the quarters

2 pennies + 1 nickel + 2 quarters + (2 dimes + 1 nickel) = 8

Do it again because you haven't gotten to 11 yet - break up another quarter.

2 pennies + 1 nickel + 1 quarter +(2 dimes + 1 nickel) + (2 dimes + 1 nickel) = 10 coins

If you break up another quarter, that will result in a minimum of at LEAST 3 coins. That would be adding too many to make 11. So break up the next largest coin...in this case, a dime.

2 pennies + 1 nickel + 1 quarter + 2 dimes + 1 nickel + (1 dime + 3 nickels) = 11 coins

Your answer is:
2 pennies
5 nickels
3 dimes
1 quarter

Answer 4

I hope you're writing from the US.
First, we need at least 2 pennies, so let's look for 9 coins that add up to 80 cents.
8 dimes is 8 coins, but 7 times and 2 nickels is also 80 cents, and is 9 coins?

So, 2 pennies, 2 nickels, and 7 dimes.

Answer 5

First, we need at least 2 pennies, so let's look for 9 coins that add up to 80 cents.
8 dimes is 8 coins, but 7 times and 2 nickels is also 80 cents, and is 9 coins?
there r lots of answers

Answer 6

7 dimes= 70 cents
2 nickels= 10 cents
2 pennies= 2 cents
11 coins= 82 cents

Answer 7

2 nickels 7 dimes 2 pennies

Answer 8

We have already established that there are two pennies, so now we need another nine coins that equal eighty two cents. So that could be Seven dimes and two nickes, and two pennies or 2 pennies, 5 nickels,3 dimes, 1 quarter.

Answer 9

There are several answers. I think it's a more interesting question if you are told that Pierre has only pennies, nickles, dimes, and quarters, and he has at least one of each. Then I think there is only one answer:

1 quarter
3 dimes
5 nickles
2 pennies

Answer 10

1 50 cent piece
2 dimes
1 nickel
7 pennies