You can put this solution on YOUR website! Log7 37/49 + log7 343 - log7 37/7
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=
=
=
=
= 2
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Or do it like this:
log((37/49)*343/(37/7))
= log(37) - log(49) + log(343) - log(37) + log(7) --- All base 7
= log(37 - 2 + 3 - log(37) + 1
= 2