Square root recognition: Evaluate √0.121 and choose the closest value.

Introduction / Context:
We compute the square root of a decimal 0.121 = 121/1000. Unlike 0.0121 (which is 0.11^2), this value is larger and needs an appropriate approximation.

Given Data / Assumptions:

• Number: 0.121 = 121/1000.
• We want √0.121.

Concept / Approach:
Use a decimal approximation: √0.121 is between √0.09 (= 0.3) and √0.16 (= 0.4). Closer to 0.11? No—note 0.11^2 = 0.0121, not 0.121.

Step-by-Step Solution:

Verification / Alternative check:
More accurate value: √0.121 ≈ 0.348552; option 0.347 differs by about 0.0016, within typical rounding.

Why Other Options Are Wrong:

• 0.11 corresponds to √0.0121, not √0.121.
• 1.1 and 0.011 are off by factors of 10 or 100.
• 0.321 is not close enough.

Common Pitfalls:
Confusing 0.121 with 0.0121; always square the guess to verify.

Final Answer:
0.347