Question

Using log tables evaluate 0.6283×17.85

Answer 1

Wow, you still have log tables?

if you insist, but I will use my calculator and round the results to 4 decimals
since most of the log tables they had in the 60s and 70s had only 4 decimals

let x = 0.6283×17.85
log x = log(0.6283×17.85)
= log 0.6283 + log 17.85
= (-1 + .7982) + (1 + .2516) , I remembered all that mantissa stuff
= -.2018 + 1.2516
log x = 1.0498
x = 10^1.0498

I suppose you also had antilog tables
x = 10^1.0498
= 10^1 * 10^.0498 , find .0498 in the anti-log tables
= 10 * 1.12150
= 11.2150