Finding the Fourth Proportional to 1,290,005.91, 1,780,163.32 and 831,139.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,290,005.91 : 1,780,163.32 = 831,139.83 : x
2. Step 2: Convert to fraction form
   1,290,005.91/1,780,163.32 = 831,139.83/x
3. Step 3: Cross multiply
   1,290,005.91x = 1,780,163.32 × 831,139.83
4. Step 4: Simplify right side
   1,290,005.91x = 1,479,564,626,100.52
5. Step 5: Solve for x
   x = 1,479,564,626,100.52/1,290,005.91
6. Step 6: Final answer
   x = 1,146,944.07