Final answer:
The correct answer is option A. To calculate the area of a playground, you must use the appropriate formula based on the shape. For a circular playground, the correct formula is A = πr², with the final answer rounded to the same number of significant figures as the given dimensions.
Step-by-step explanation:
When attempting to find the area of a playground, it is important to choose the correct formula based on the shape of the playground. The playground can be of various shapes such as rectangle, circle, square, or even an irregular shape. The standard formulas for calculating area are based on these shapes.
For example, the formula to find the area of a circle is A = πr², where 'A' is the area and 'r' is the radius of the circle. Using a calculator with eight-digit output, if you have a circle with a radius of 1.2 meters, calculating its area can be approached by squaring the radius and multiplying by Pi (π). This will give you an area of 4.5238934 m². However, since the radius has only two significant figures, the answer should also be rounded to two significant figures, resulting in an area of 4.5 m².
For other shapes, such as rectangles or squares, the formulas will be different. A rectangle's area is found by multiplying its length by its width (A = length × width), and a square's area is found by squaring one of its sides (A = s²). In case of a triangle, the area would be half the product of its base and height (A = 1/2 × base × height).
Therefore, if the playground is a circle, the correct option for the expression to find its area is A. Area = πr².