Finding the Third Proportional to 616,900 and 840,421.50

Step by Step Solution

1. Step 1: Write the proportion equation
   616,900 : 840,421.50 = 840,421.50 : x
2. Step 2: Convert to fraction form
   616,900/840,421.50 = 840,421.50/x
3. Step 3: Cross multiply
   616,900x = 840,421.50 × 840,421.50
4. Step 4: Simplify right side
   616,900x = 706,308,297,662.25
5. Step 5: Solve for x
   x = 706,308,297,662.25/616,900
6. Step 6: Final answer
   x = 1,144,931.59