Answer :
9 Nickels, 8 Dimes...here is how i work it out!
d + n = 17
0.1d + 0.05n = 1.25
d = 17 - n
0.1 (17 - n) + 0.05n = 1.25
1.7 - 0.1n + 0.05n = 1.25
1.7 - 0.05n = 1.25
-0.05n = -0.45
n = 9
9 Nickels, 8 Dimes
d + n = 17
0.1d + 0.05n = 1.25
d = 17 - n
0.1 (17 - n) + 0.05n = 1.25
1.7 - 0.1n + 0.05n = 1.25
1.7 - 0.05n = 1.25
-0.05n = -0.45
n = 9
9 Nickels, 8 Dimes