Finding the Fourth Proportional to 585,136.72, 807,484 and 316,864.72

Step by Step Solution

1. Step 1: Write the proportion equation
   585,136.72 : 807,484 = 316,864.72 : x
2. Step 2: Convert to fraction form
   585,136.72/807,484 = 316,864.72/x
3. Step 3: Cross multiply
   585,136.72x = 807,484 × 316,864.72
4. Step 4: Simplify right side
   585,136.72x = 255,863,191,564.48
5. Step 5: Solve for x
   x = 255,863,191,564.48/585,136.72
6. Step 6: Final answer
   x = 437,270.78