Algebra-1

Question Analysis
This question involves finding the frequency of a missing category (biking) in a survey, using the total number of respondents.
The main focus is on applying the property that the sum of all category frequencies equals the total number of observations.

Key Concept Explanation
Frequency of a Missing Category: When the total number of observations is known, the frequency of an unlisted category is calculated by subtracting the sum of the known frequencies from the total.

Step-by-Step Solution
Calculate the sum of known frequencies: 8 (walk) + 12 (bus) = 20.
Subtract this sum from the total number of students surveyed: 30 - 20 = 10.