Finding the Third Proportional to 420,116.50 and 645,749

Step by Step Solution

1. Step 1: Write the proportion equation
   420,116.50 : 645,749 = 645,749 : x
2. Step 2: Convert to fraction form
   420,116.50/645,749 = 645,749/x
3. Step 3: Cross multiply
   420,116.50x = 645,749 × 645,749
4. Step 4: Simplify right side
   420,116.50x = 416,991,771,001
5. Step 5: Solve for x
   x = 416,991,771,001/420,116.50
6. Step 6: Final answer
   x = 992,562.23