(Apologies for the delay on this. I just noticed that it didn't publish properly when I posted it on Friday.)
How can you make 83 cents with 7 coins?
How can you make 17 cents with 5 coins?
How can you make 39 cents with 8 coins?
How can you make 99 cents with 12 coins?
How can you make 50 cents with 6 coins?