We can't do it using just 1 quarter because then we'd have
to have the remaining 70 cents with 6 coins, and 6 dimes is
only 60 cents. So we can't use just one quarter.
If we use just 2 quarters, we have to have the remaining
45 cents with 5 coins, which we can have with 4 dimes and
1 nickel. That's the only way with 2 quarters. So one way is
1. 2 quarters, 4 dimes, and 1 nickel.
If we use 3 quarters, we have to have the remaining
20 cents with 4 coins, which we can have with 4 nickels.
That's the only way with 3 quarters. So a second way is
2. 3 quarters and 4 nickels.
Half dollars (50 cent pieces) are not in circulation, but
if we can use 1 half dollar, then we have to have the remaining
45 cents with 6 coins. The only way we can have that is with
3 dimes and 3 nickels. So a third way is
3. 1 half dollar, 3 dimes, and 3 nickels.
So there are three ways, if your teacher allows you to use a
half dollar. Otherwise there are only 2 ways.
Edwin
