Finding the Third Proportional to 318,921 and 493,501.50

Step by Step Solution

1. Step 1: Write the proportion equation
   318,921 : 493,501.50 = 493,501.50 : x
2. Step 2: Convert to fraction form
   318,921/493,501.50 = 493,501.50/x
3. Step 3: Cross multiply
   318,921x = 493,501.50 × 493,501.50
4. Step 4: Simplify right side
   318,921x = 243,543,730,502.25
5. Step 5: Solve for x
   x = 243,543,730,502.25/318,921
6. Step 6: Final answer
   x = 763,649.09