Answer:
No.
Step-by-step explanation:
Let d represent the number of dimes. Then the number of quarters (according to the friend) is d+8. The total value is
... 10d +25(d+8) = 280 . . . . in cents
... 35d + 200 = 280 . . . . . . eliminate parentheses
... 35d = 80 . . . . . . . . . . . . . subtract 200
... d = 80/35 = 16/7 = 2 1/7 . . . . . not a realistic number of coins
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The difference between the number of quarters and the number of dimes may be any multiple of 7.
