We can go ahead with considering n to be 1(+ve int)
then the stimulus= 7^7*3*2/10
Now units digit of 7^7=3
and 3*3*2=18/10 will leave us remainder as 8
thats the ans !
question on remainder..
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netigen
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Silvia,
the way to solve these type of Qs is to realize that the power of 7 will have repeating unit digits for e.g.
unit digit of 7^1 = 7
unit digit of 7^2 = 9
unit digit of 7^3 = 3
unit digit of 7^4 = 1
unit digit of 7^5 = 7
unit digit of 7^6 = 9
unit digit of 7^7 = 3
unit digit of 7^8 = 1
We find that the unit digit repeats in cycles of 4
power of 7 is of the form 4n+3 which means that the unit digit will be 3
6^n will have unit digit = 6
so we get 6 x 3 = 8 in the units digit which will leave a remainder of 8
the way to solve these type of Qs is to realize that the power of 7 will have repeating unit digits for e.g.
unit digit of 7^1 = 7
unit digit of 7^2 = 9
unit digit of 7^3 = 3
unit digit of 7^4 = 1
unit digit of 7^5 = 7
unit digit of 7^6 = 9
unit digit of 7^7 = 3
unit digit of 7^8 = 1
We find that the unit digit repeats in cycles of 4
power of 7 is of the form 4n+3 which means that the unit digit will be 3
6^n will have unit digit = 6
so we get 6 x 3 = 8 in the units digit which will leave a remainder of 8
