Significant figures and rounding rules Decide whether this rounding statement is correct: “The number 24.5, rounded to two significant digits, becomes 25.”

Introduction / Context:
Significant figures communicate the precision of measured or computed values. Rounding properly preserves the intended precision without overstating certainty. This is crucial in tolerance stacks, component value reporting, and lab notes.

Given Data / Assumptions:

• Original value: 24.5 (three significant digits).
• Target: two significant digits.
• Standard rounding-to-nearest with 5 causing a round up of the preceding digit.

Concept / Approach:
To round to two significant digits, keep the first two nonzero digits and examine the next digit. If the next digit is 5 or greater, increase the last kept digit by one; otherwise, leave it. The position of the decimal point and whether trailing zeros are written can affect how many significant figures are perceived, but the rounded numeric value follows these rules consistently.

Step-by-Step Solution:

Verification / Alternative check:
Compare with rounding to one significant digit: 24.5 → 20 (since the next digit “4” is less than 5 after the “2”). For three significant digits, 24.5 remains 24.5. The two-digit target clearly yields 25 by standard rules.

Why Other Options Are Wrong:

Common Pitfalls:
Confusing significant digits with decimal places; assuming “.0” always increases sig figs; using bank rounding rules unintentionally instead of standard round-to-nearest for technical reporting.

Final Answer:
Correct