Finding the Third Proportional to 358,905 and 557,320.50

Step by Step Solution

1. Step 1: Write the proportion equation
   358,905 : 557,320.50 = 557,320.50 : x
2. Step 2: Convert to fraction form
   358,905/557,320.50 = 557,320.50/x
3. Step 3: Cross multiply
   358,905x = 557,320.50 × 557,320.50
4. Step 4: Simplify right side
   358,905x = 310,606,139,720.25
5. Step 5: Solve for x
   x = 310,606,139,720.25/358,905
6. Step 6: Final answer
   x = 865,427.17