given log 2 base 7 is 0,3562 and log 3 base 7 is 0,5646 evaluate log 42 base 7 without using calculator or tables

Answer 1

42 = 2*21 = 2 * 3 * 7 (lucky :)
so
log 42 = log 2 + log 3 + log 7
all base 7
but what is log 7 base 7
7^log 7 = 7 but that is 7^1
so log 7 = 1 if base 7
so
log 42 = log 2 + log 3 + 1
no way I will add those numbers without my machine :)