Given below are two statements: Statement I: Minimum number of bits required…

2020

Given below are two statements:

Statement I: Minimum number of bits required to store any 3-digit decimal number is 10.

Statement II: The data in a digital computer is stored in terms of bits/ bytes where one PetaByte is equal to 250 bits.

Choose the correct answer from the options given below:

  1. A.

    Both Statement I and Statement II are true

  2. B.

    Both Statement I and Statement II are false

  3. C.

    Statement I is correct but Statement II is false

  4. D.

    Statement I is incorrect but Statement II is true

Attempted by 24 students.

Show answer & explanation

Correct answer: C

Concept

To store a value in binary you need enough bits to give each possible value a distinct pattern: n bits produce 2n patterns, so storing values up to a maximum M needs the smallest n with 2n > M. Separately, the storage-unit ladder is byte-based: 1 byte = 8 bits, and 1 PetaByte = 250 bytes (strictly a pebibyte, since standards bodies reserve “petabyte” for a decimal quantity, but this question follows the common exam convention treating the two as equal), so a PetaByte equals 250 x 8 = 253 bits, not 250 bits.

Applying it to each statement

  1. Statement I — the bit count. A 3-digit decimal number runs up to 999. Since 29 = 512 covers only 0-511 and 210 = 1024 covers 0-1023, the value 999 fits in 10 bits but not in 9. So the minimum is 10 bits — Statement I is true.

  2. Statement II — the unit. One PetaByte is 250 bytes. Converting to bits multiplies by 8: 250 x 23 = 253 bits. Equating one PetaByte with 250 bits drops the byte-to-bit factor of 8, so Statement II is false.

Cross-check

Statement I true and Statement II false together point to: “Statement I is correct but Statement II is false.” As a sanity check, 999 in binary is 1111100111 — exactly 10 binary digits — and 250 bits would be only one-eighth of a PetaByte (an eighth of 1 PB = 128 TB), confirming the unit in Statement II is wrong.

Explore the full course: Nta Ugc Net Paper 1