Question

What will be the digit in the unit place in product (3807)^194 × (932)^84 ?

(a) 9
(b) 1
(c) 2
(d) 4
(e) 7

Correct Answer is 4 Explain how?

Answer 1

hey mate here's ur answer...,,

7 * 7 = ends with 9;

7 * 7 * 7 * 7 = ends with 9 * 9 = 1

so any no with the last digit 7 raised to the power 4n where n can be 0,1, 2, 3, 4,5 ... so on ends with 1

so 3807 ^ 194 will end with 9 since 194 = 192 + 2 where 192 is a multiple of 4 so 3807 ^ 192 ends with 1 but 3807 ^ 194 ends with 1 * 7 * 7 = 9;

similarly with 2 we can see this behaviour:

2 * 2 * 2 * 2 = ends with 6

so 2 ^ 4m where m = 0,1,2,3,4,5...so on always ends with 6

since 84 is a multiple of 4 932 ^ 84 ends with 6

so 9 * 6 ends with 4.

.....

Step-by-step explanation:

hope it helps u

mark brainliest...

I really need it