Answer:
0.5637
Explanation:
We'll use the change of base formula:
log to the base a of x = [log to the base 10 of x] / [log to the base 10 of a].
In this case, the base is a = 8 and x is 40.
Thus, log to the base 8 of 40 =
log to the base 10 of 40
-----------------------------------------
log to the base 10 of 8
and this comes out to:
log 40 1.60206
log to the base 8 of 40 = --------------- = ----------------- = 0.5637
log 8 0.90309