Finding the Fourth Proportional to 1,189,441.58, 1,641,434.31 and 645,578.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,189,441.58 : 1,641,434.31 = 645,578.15 : x
2. Step 2: Convert to fraction form
   1,189,441.58/1,641,434.31 = 645,578.15/x
3. Step 3: Cross multiply
   1,189,441.58x = 1,641,434.31 × 645,578.15
4. Step 4: Simplify right side
   1,189,441.58x = 1,059,674,116,989.16
5. Step 5: Solve for x
   x = 1,059,674,116,989.16/1,189,441.58
6. Step 6: Final answer
   x = 890,900.52