Difficulty: Easy
Correct Answer: 11
Explanation:
Introduction / Context:This problem tests symbolic substitution and correct use of operator precedence (BODMAS/PEMDAS). We replace the given letters with their intended arithmetic operators and then evaluate with standard precedence rules.
Given Data / Assumptions:
Concept / Approach:First perform division and multiplication, then handle addition/subtraction. Parentheses are not present, so no grouping overrides the default precedence.
Step-by-Step Solution:
Replace symbols: 40 B 8 T 6 M 3 K 4 → 40 ÷ 8 − 6 + 3 × 4. Compute ÷ and ×: 40 ÷ 8 = 5; 3 × 4 = 12. Now evaluate: 5 − 6 + 12 = (5 − 6) + 12 = −1 + 12 = 11.Verification / Alternative check:Reordering incorrectly (left-to-right without precedence) would give a wrong value; a quick calculator check with the same precedence confirms 11.
Why Other Options Are Wrong:Values like 19 or 23 arise from ignoring precedence (e.g., adding before multiplying). −31 is the result of multiplying both 4 and 8 before subtracting from 7-like patterns, which do not apply here.
Common Pitfalls:Misreading K as division or treating all operations strictly left-to-right. Always apply ×/÷ before +/− unless parentheses dictate otherwise.
Final Answer:11.
Discussion & Comments