Question

The mean of four numbers is 300. If the mean of two of the four numbers is 310, then the mean of the other two numbers is

• A. 290
• B. 295
• C. 300
• D. 305

Hint:

Always convert mean into total sum before splitting groups.

Answer 1

The Correct Option is A

Concept: Use total sum approach. Explanation: Mean of 4 numbers = 300 Total sum: \[ 4 \times 300 = 1200 \] Mean of 2 numbers = 310 Sum of those 2: \[ 2 \times 310 = 620 \] Remaining sum: \[ 1200 - 620 = 580 \] Mean of remaining 2: \[ 580 \div 2 = 290 \]