In a class, approximately 4 out of every 5 students are left-handed. If there are exactly 40 students in the class, how many of them would be left-handed according to this ratio?

Introduction:
This is a simple ratio and proportion question. You are told that 4 out of every 5 students are left-handed, and you must use this information to find the exact number of left-handed students in a class of 40.

Given Data / Assumptions:

• Ratio of left-handed students to total students is 4 : 5.
• Total number of students in the class = 40.
• We assume the ratio applies exactly to this class.
• We need to find the number of left-handed students.

Concept / Approach:
The statement “4 out of 5” corresponds to the fraction 4/5 of the total. Thus, the number of left-handed students is (4/5) of 40. This is a direct application of ratios or percentages (since 4/5 is 80%).

Step-by-Step Solution:
Step 1: Write the fraction representing left-handed students.Left-handed fraction = 4/5.Step 2: Apply it to the total number of students.Number of left-handed students = (4/5) * 40.Step 3: Compute the product.(4/5) * 40 = 4 * 8 = 32.So, there are 32 left-handed students.

Verification / Alternative check:
You can also think in terms of groups of 5 students. In each group of 5, 4 are left-handed. 40 students can be divided into 8 groups of 5. Each group contributes 4 left-handed students, so total left-handed = 8 * 4 = 32.

Why Other Options Are Wrong:
40 would imply everyone is left-handed, which does not match 4 out of 5. 45 exceeds the total number of students. 30 or 28 would correspond to fractions smaller than 4/5 of 40. Only 32 exactly reflects the 4/5 proportion of 40 students.

Common Pitfalls:
Some students misread “4 out of 5” as 4 + 5 instead of a ratio, or incorrectly compute 40 * (5/4). Always remember that “4 out of 5” means 4/5 of the total quantity.

Final Answer:
According to the given ratio, 32 students would be left-handed.