Difficulty: Medium
Correct Answer: 5
Explanation:
Introduction / Context:
This question checks decoding of swapped mathematical operators and correct evaluation using normal precedence rules. The expression must be translated into standard operations first, and only then computed.
Given Data / Assumptions:
Concept / Approach:
Convert each coded operator to its real meaning. Then compute the decoded expression using multiplication/division before addition/subtraction.
Step-by-Step Solution:
Original: 80 x 16 ÷ 4 + 2 - 8
Decode operators one by one:
x means /, so: 80 / 16
÷ means -, so between 16 and 4 it becomes: - 4
+ means *, so between 4 and 2 it becomes: * 2
- means +, so between 2 and 8 it becomes: + 8
Decoded expression: 80 / 16 - 4 * 2 + 8
Compute division: 80 / 16 = 5
Compute multiplication: 4 * 2 = 8
Now: 5 - 8 + 8 = 5
Verification / Alternative check:
Notice that - (4*2) + 8 cancels out to 0, leaving only 80/16 = 5. This confirms the answer quickly.
Why Other Options Are Wrong:
64: comes from treating x as multiplication.
11: from incorrect decoding of - as subtraction.
30: from computing without precedence or wrong mapping.
13: from partial cancellation errors.
Common Pitfalls:
Evaluating the coded expression directly, forgetting to decode every operator, or doing subtraction before multiplication causes incorrect results.
Final Answer:
5
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