Finding the Fourth Proportional to 751,139.72, 1,036,007.38 and 521,697.31

Step by Step Solution

1. Step 1: Write the proportion equation
   751,139.72 : 1,036,007.38 = 521,697.31 : x
2. Step 2: Convert to fraction form
   751,139.72/1,036,007.38 = 521,697.31/x
3. Step 3: Cross multiply
   751,139.72x = 1,036,007.38 × 521,697.31
4. Step 4: Simplify right side
   751,139.72x = 540,482,263,286.15
5. Step 5: Solve for x
   x = 540,482,263,286.15/751,139.72
6. Step 6: Final answer
   x = 719,549.57