Finding the Third Proportional to 3,586.78 and 5,120.72

Step by Step Solution

1. Step 1: Write the proportion equation
   3,586.78 : 5,120.72 = 5,120.72 : x
2. Step 2: Convert to fraction form
   3,586.78/5,120.72 = 5,120.72/x
3. Step 3: Cross multiply
   3,586.78x = 5,120.72 × 5,120.72
4. Step 4: Simplify right side
   3,586.78x = 26,221,760.52
5. Step 5: Solve for x
   x = 26,221,760.52/3,586.78
6. Step 6: Final answer
   x = 7,310.67