A. 280
B. 270
C. 283
D. 286
🧠 Explanation:
Given: Average of 277, 278, 279, 280, 281, 282
Step 1: Use mean of arithmetic sequence = (first + last) ÷ 2
Step 2: (277 + 282) ÷ 2 = 559 ÷ 2 = 279.5
Step 3: Alternatively, sum all = 1677; divide by 6 = 279.5
Check: Central values 279 and 280 average to 279.5 (even count)
Final Answer: 280
