Answer:
(Q, D, N, P) = (0, 7, 4, 2) or (1, 3, 7, 2)
Step-by-step explanation:
Let the numbers of coins be Q, D, N, P
We have:
Q + D + N + P = 13
25Q + 10D + 5N + P = 92
Obviously, P = 2, so
Q + D + N = 11 (1)
25Q + 10D + 5N = 90
Divide by 5 and get
5Q + 2D + N = 18 (2)
(2) - (1), get
4Q + D = 7
Let D = 7, Q = 0, from (1), N = 4, so the set is (Q, D, N, P) = (0, 7, 4, 2)
Let D = 3, Q = 1, from (1), N = 7, so the set is (Q, D, N, P) = (1, 3, 7, 2)
If D = 6, 5, 4, 2, 1, 0, Q is not an integer, these can be ignored.
