What is the unit digit in(795 – 358)?

Question:
What is the unit digit in(795 – 358)?

[A].

0

[B].

4

[C].

6

[D].

7

Answer: Option B

Explanation:

Unit digit in 795 = Unit digit in [(74)23 x 73]

= Unit digit in [(Unit digit in(2401))23 x (343)]

= Unit digit in (123 x 343)

= Unit digit in (343)

= 3

Unit digit in 358 = Unit digit in [(34)14 x 32]

= Unit digit in [Unit digit in (81)14 x 32]

= Unit digit in [(1)14 x 32]

= Unit digit in (1 x 9)

= Unit digit in (9)

= 9

Unit digit in (795 – 358) = Unit digit in (343 – 9) = Unit digit in (334) = 4.

So, Option B is the answer.