Question Details

The sum of all the digits of the number  ( 10 50 + 10 25 123 ) , is

Options

A

212

B

221

C

324

D

255

Show Answer

Correct Answer :

Option B

221

Solution :

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The correct option is 221.


To find the sum of all the digits of the number:

(1050+1025123)


Let us break down the calculation step-by-step:


Step 1: Simplify the term 1025123

The term 1025 represents 1 followed by 25 zeros (a 26-digit number). When we subtract 123 from 1025, we get a 25-digit number:

1025123=999999877


Analyzing the digits of this 25-digit result:

• The last 3 digits are 8, 7, 7 (since 1000 − 123 = 877).

• The remaining 22 digits (from the 4th digit to the 25th digit from the right) are all 9s.


Step 2: Add 1050 to the result

The term 1050 adds a single 1 at the 51st position from the right. The positions between the 26th digit and the 50th digit are all 0s.


Thus, the full number consists of:

• One 1 at the highest place value (1050 position)

25 zeros between the 26th and 50th places

22 nines (9s)

• One 8

• Two 7s


Step 3: Calculate the sum of all digits

Sum of digits = (1) + (25 × 0) + (22 × 9) + 8 + 7 + 7


Sum of digits = 1 + 0 + 198 + 22


Sum of digits = 221


Therefore, the sum of all the digits of the given number is 221.

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