Finding the Fourth Proportional to 499,870.17, 689,103.18 and 356,381.10

Step by Step Solution

1. Step 1: Write the proportion equation
   499,870.17 : 689,103.18 = 356,381.10 : x
2. Step 2: Convert to fraction form
   499,870.17/689,103.18 = 356,381.10/x
3. Step 3: Cross multiply
   499,870.17x = 689,103.18 × 356,381.10
4. Step 4: Simplify right side
   499,870.17x = 245,583,349,301.90
5. Step 5: Solve for x
   x = 245,583,349,301.90/499,870.17
6. Step 6: Final answer
   x = 491,294.27