Difficulty: Easy
Correct Answer: None of these
Explanation:
Introduction / Context:
This is a standard “selections with upper bounds” problem where we count choices independently for each type and multiply. We are not forming permutations or combinations of identical items; we are counting how many different selection vectors (b, a, o) are possible given caps per type.
Given Data / Assumptions:
Concept / Approach:
For each fruit, the number of possible counts equals (max + 1). By the rule of product for independent decisions, multiply the per-type possibilities together.
Step-by-Step Solution:
Verification / Alternative check:
Enumerating edges (all-max, all-min, mixed) confirms counts fall within the independent ranges, reinforcing 60.
Why Other Options Are Wrong:
39, 315, or 512 do not match the product of simple ranges (4*5*3). 512 typically appears for unconstrained binary choices over 9 items, which is not this setting.
Common Pitfalls:
Confusing “ways to select” with permutations; forgetting to include the zero-choice option per fruit.
Final Answer:
None of these (the correct count is 60).
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