Finding the Fourth Proportional to 390,109.96, 585,185.10 and 123,891.40

Step by Step Solution

1. Step 1: Write the proportion equation
   390,109.96 : 585,185.10 = 123,891.40 : x
2. Step 2: Convert to fraction form
   390,109.96/585,185.10 = 123,891.40/x
3. Step 3: Cross multiply
   390,109.96x = 585,185.10 × 123,891.40
4. Step 4: Simplify right side
   390,109.96x = 72,499,401,298.14
5. Step 5: Solve for x
   x = 72,499,401,298.14/390,109.96
6. Step 6: Final answer
   x = 185,843.50