Hello,
I guess you wanted to use Fermat's little theorem. Unfortunately, this only works if 77 is a prime number.
Otherwise, you can use Euler's theorem which states that :
With the Euler's totient function, defined as :
(p designing prime numbers)
(the first one can be a deduction of this one)
(with q a prime number)
As 77 is 11x7,
=>
Well,
Division of 100.000 by 60.
i'll say that 100 is 60x16+40
So 100.000 is 60x16000+40.000
So you can throw off this term...
There is 40.000 remaining : find the remain of 40.000 in the division by 60 (i've shown steps above, because i'm too lazy to take a calculator )