Finding the Third Proportional to 402,420 and 852,811.50

Step by Step Solution

1. Step 1: Write the proportion equation
   402,420 : 852,811.50 = 852,811.50 : x
2. Step 2: Convert to fraction form
   402,420/852,811.50 = 852,811.50/x
3. Step 3: Cross multiply
   402,420x = 852,811.50 × 852,811.50
4. Step 4: Simplify right side
   402,420x = 727,287,454,532.25
5. Step 5: Solve for x
   x = 727,287,454,532.25/402,420
6. Step 6: Final answer
   x = 1,807,284.56