Question

The average (arithmetic mean) number of trees per acre in a 40-acre plot is 140.
If a 10-acre section of the plot contains 90 trees per acre, how many trees are
there in the remaining 30 acres?

• A. \( \text{5,700} \)
• B. \( \text{4,700} \)
• C. \( \text{4,200} \)
• D. \( \text{3,600} \)
• E.

Hint:

Subtract section trees from total.

Answer 1

The Correct Option is C

Step 1: Total trees in 40 acres = average per acre × total acres
= 140 × 40 = 5,600.
Step 2: Trees in 10-acre section = 90 × 10 = 900.
Step 3: Trees in remaining 30 acres = total trees - section trees
= 5,600 - 900 = 4,200.
Step 4: (C) 4,200 matches the calculation.