+752 Suppose that a and b are digits in base d > 6 such that 
. Find a_d - b_d in base d. thanks! 
63_7 + 66_7 = 162_7
6_7 - 3_7 = 3_7
Note: The first base I tried was base 7. I converted 162_7 to base 10 = 93. Then I tried 2 numbers that add up to 93. I tried 45 + 48 = 93. Then I converted 45 to base 7 =63. And similarly, converted 48 to base 7 = 66. Then added 63 + 66 (base 7) =162_7. That is how I arrived at the answer above.
