Finding the Fourth Proportional to 810,570.42, 1,216,065.72 and 431,178.72

Step by Step Solution

1. Step 1: Write the proportion equation
   810,570.42 : 1,216,065.72 = 431,178.72 : x
2. Step 2: Convert to fraction form
   810,570.42/1,216,065.72 = 431,178.72/x
3. Step 3: Cross multiply
   810,570.42x = 1,216,065.72 × 431,178.72
4. Step 4: Simplify right side
   810,570.42x = 524,341,660,585.48
5. Step 5: Solve for x
   x = 524,341,660,585.48/810,570.42
6. Step 6: Final answer
   x = 646,879.84