You could have 1 dime, 12 nickels and 930 pennies.
You could have 9 quarters, 24 dimes, 35 nickels and 360 pennies.
You could have 33 quarters, 8 dimes, and 19 nickels.
Many, many, many ways!
Notice thet you didn't say anything about not having other coins
besides nickels and dimes. You just said there are 11 more nickels
than dimes. That is true about all those solutions above, and
there are many other possibilities.
Be sure to state if the bank only contains nickels and dimes.
If you meant that there are only nickels and dimes, then
Let d = the number of dimes
Then the number of nickels is d+11
The equation comes from
0.05(d+11) + 0.10(d) = 10.00
Clear of decimals by multiplying all the decimals by 100.
5(d+11) + 10d = 1000
5d + 55 + 10d = 1000
15d + 55 = 1000
15d = 945
d = 63
So there are 63 dimes and
The number of nickels is d+11 = 63+11 = 74 nickels.
Edwin