Final answer:
To find the diameter of a U.S. 50-cent piece with a given area, we use the area of a circle formula and solve for the radius. Doubling the radius gives us the diameter, which is 30.6 mm when rounded to the nearest tenth.
Step-by-step explanation:
The student's question involves finding the diameter of a U.S. 50-cent piece with an area of 735 square millimeters, using 3.14 for pi. To calculate the diameter of a circle when you have the area, you can use the formula A = πr², where A is the area and r is the radius. Solving for the radius, we get r = √(A/π). Once you have the radius, you can double it to find the diameter (D = 2r).
To apply this to the half-dollar coin:
1. A = 735 mm²
2. π = 3.14
3. r = √(735 mm² / 3.14) = √(234.076 mm²) = 15.3 mm
4. D = 2r = 2(15.3 mm) = 30.6 mm
Thus, the diameter of the U.S. 50-cent piece, rounded to the nearest tenth, is 30.6 mm.