Difficulty: Easy
Correct Answer: 117
Explanation:
Introduction / Context:This is a direct rectangle area question. When a floor or region is rectangular, its area is found by multiplying its length and breadth. The phrase “square units” means the numeric answer should be expressed as a count of unit squares that can cover the rectangle, so the multiplication result is the area.
Given Data / Assumptions:
Concept / Approach:Use area = 13 * 9. This is a single-step multiplication problem with no unit conversion needed.
Step-by-Step Solution:
Step 1: Area = length * breadth Step 2: Area = 13 * 9 Step 3: 13 * 9 = (10 * 9) + (3 * 9) = 90 + 27 = 117 square unitsVerification / Alternative check:You can verify by reversing: if area is 117 and one side is 13, the other side must be 117/13 = 9, which matches the given breadth. That consistency confirms the multiplication is correct.
Why Other Options Are Wrong:
97, 107, 127: are not products of 13 and 9, and do not represent the correct rectangle area. 135: would be 15 * 9 or 13 * 10.38, not 13 * 9. Only 117 is the exact area for a 13-by-9 rectangle.Common Pitfalls:Some learners mistakenly add 13 + 9 instead of multiplying, which gives 22, not an area. Another mistake is confusing area with perimeter (2*(13+9)=44). Always choose multiplication for area of rectangles, and addition-based formula for perimeter.
Final Answer:117
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