Verified answer

a1 + 132d / a1 + 4d = 17

a1 + 132d= 17a1 + 68d

16a1= 64d

a1=4d

a25=a1 + 24d=4d + 24d= 28d

a47=a1 + 46d= 4d + 46d= 50d

28d/50d= 28/50= 14/25