Difficulty: Easy
Correct Answer: 280
Explanation:
Introduction / Context:
This problem is about interpreting percentage-based allocations relative to a fixed reference count (the number of students). Both students and teachers receive sweets calculated as percentages of the student count, not of recipients.
Given Data / Assumptions:
Concept / Approach:
Compute per-recipient sweets first, since the percentage base is the number of students. Then multiply by the number of recipients in each group and add the results to obtain the total sweets needed.
Step-by-Step Solution:
Per student = 0.15 * 40 = 6 sweetsPer teacher = 0.20 * 40 = 8 sweetsStudents total = 40 * 6 = 240Teachers total = 5 * 8 = 40Grand total = 240 + 40 = 280 sweets
Verification / Alternative check:
Check bases: both percentages reference 40 students, not 45 total people, so the above multiplication is correct.
Why Other Options Are Wrong:
240 omits teacher sweets; 320 and 360 overshoot; 260 undercounts a subgroup.
Common Pitfalls:
Using the total people (45) as the percentage base or calculating different bases for students and teachers leads to incorrect totals.
Final Answer:
280
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