You can put this solution on YOUR website! Use change of base formula
log b (x)=log d (x)/log d (b)
use 3 as the new base
log 40 of 3= log 3 (3)/log 3 (40)
That is 1/log 3(40)
log 3(27)=3
log 3(81)=4
So log 3 (40) is between 3 and 4
1/log 3 (40) is between 1/3 and 1/4