How many different combinations of coins can total exactly $0.40?

Question

I got 31 possible combinations

Answer 1

I only got 27

P -N D Q
50 0 0 0
35 1
30 2
25 3
20 4
15 5
10 6
5 7
0 8 0 0
30 0 1 0
25 1 1
20 2 1
15 3 1
10 4 1
5 5 1
0 6 1 0
20 0 2
15 1 2
10 2 2
5 3 2
0 4 2
10 0 3
5 1 3
0 2 3
0 0 4 0
5 0 1 1
0 1 1 1

If you see only 3 numbers the last digit is 0