Question

The unit place digit in 2^50 x 5^48 – 9 is tennetiraj please help for my questions​

Answer 1

Step-by-step explanation:

Given :-

2^50 x 5^48 – 9

To find :-

The unit place digit in 2^50 x 5^48 – 9 ?

Solution :-

Given number is 2^50 x 5^48 – 9

2^50 = 2×2×2×...×(50 times)

2^1 = 2

2^2 = 4

2^3 = 8

2^4 = 16

2^5 = 32

2^6 = 64...

If you continues the unit places are 2,4,8,6.They repeat agin again

2^50 = (2^5)^10

The units place of 2^50 = 4

and 5^48

5^1 = 5

5^2 = 25

We continue like this we get always 5 in its units place

=> The unit digit in 5^48 is 5

Now

The unit place of 2^50×5^48 is

=> 4×5

=> 20

Unit place is 0

and given that

The unit place of 2^50 x 5^48 – 9

We have 0 as units place of the product and

9 is subtracted from the product

So The required digit must be 10-9 = 1

Answer:-

The unit place for the given problem is 1