Finding the Fourth Proportional to 1,189,498.72, 1,641,464.24 and 645,622.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,189,498.72 : 1,641,464.24 = 645,622.80 : x
2. Step 2: Convert to fraction form
   1,189,498.72/1,641,464.24 = 645,622.80/x
3. Step 3: Cross multiply
   1,189,498.72x = 1,641,464.24 × 645,622.80
4. Step 4: Simplify right side
   1,189,498.72x = 1,059,766,738,728.67
5. Step 5: Solve for x
   x = 1,059,766,738,728.67/1,189,498.72
6. Step 6: Final answer
   x = 890,935.59