Find the remainder when 7^103 is divided by 24

Solution) we know by the concept of mod that.....

  49 is congruent to 1 mod 24(means if 1 is subtracted fom 49 u get 48 which is divisible by 24)

 so 7^2congruent to 1 mod 24

 so 7^102congruent to 1 mod 24(raising to the power 51)

 hence the remainder when  7^102 is divided by 24 is 1  i.e. 7^102=24m+1

 so multipling by 7 both sides we have....7^103=24.7m+ 7

hence 7^103=24n + 7

so remainder is 7 (ans)