Difficulty: Medium
Correct Answer: 20
Explanation:
Given data
Concept/Approach
Form a single-variable equation in E by expressing A, B, C, D in terms of E and using the total 180.
Step-by-step calculation
A = E + 8 D = E + 5 B = D + E = (E + 5) + E = 2E + 5 C = 107 − B = 107 − (2E + 5) = 102 − 2E Sum: A + B + C + D + E = (E + 8) + (2E + 5) + (102 − 2E) + (E + 5) + E = 3E + 120 Set equal to total: 3E + 120 = 180 ⇒ 3E = 60 ⇒ E = 20
Verification
E = 20, D = 25, A = 28, B = 45, C = 62; total = 20 + 25 + 28 + 45 + 62 = 180 ✔
Common pitfalls
Forgetting that “E scored 8 fewer than A” means A = E + 8 (not E = A + 8).
Discussion & Comments