Finding the Third Proportional to 402,405 and 603,655.50

Step by Step Solution

1. Step 1: Write the proportion equation
   402,405 : 603,655.50 = 603,655.50 : x
2. Step 2: Convert to fraction form
   402,405/603,655.50 = 603,655.50/x
3. Step 3: Cross multiply
   402,405x = 603,655.50 × 603,655.50
4. Step 4: Simplify right side
   402,405x = 364,399,962,680.25
5. Step 5: Solve for x
   x = 364,399,962,680.25/402,405
6. Step 6: Final answer
   x = 905,555.26