Finding the Third Proportional to 287,220.50 and 402,486

Step by Step Solution

1. Step 1: Write the proportion equation
   287,220.50 : 402,486 = 402,486 : x
2. Step 2: Convert to fraction form
   287,220.50/402,486 = 402,486/x
3. Step 3: Cross multiply
   287,220.50x = 402,486 × 402,486
4. Step 4: Simplify right side
   287,220.50x = 161,994,980,196
5. Step 5: Solve for x
   x = 161,994,980,196/287,220.50
6. Step 6: Final answer
   x = 564,009.12