660, expressed in binary, is 1010010100. The on-bits represent powers of 2 that are: 2, 4, 7 and 9. The bases of the powers given in the puzzle are 1, 4, 1 again, and 3.
Now, the 9 that we need is a multiple of the 3 we have already, so a could be 3 as 8^3 is 2^9 = 512.
The 4 that we need is already there, as 16; just make c = 1.
The 2 and the 7 need be assigned; either b is 2 and d is 7 or vice versa.
(a, b, c, d) = (3, 2, 1, 7) or
(a, b, c, d) = (3, 7, 1, 2)
|
|
Posted by Charlie
on 2023-08-10 08:32:04 |
solution
