Finding the Fourth Proportional to 1,349.31, 1,861.94 and 789.71

Step by Step Solution

1. Step 1: Write the proportion equation
   1,349.31 : 1,861.94 = 789.71 : x
2. Step 2: Convert to fraction form
   1,349.31/1,861.94 = 789.71/x
3. Step 3: Cross multiply
   1,349.31x = 1,861.94 × 789.71
4. Step 4: Simplify right side
   1,349.31x = 1,470,385.30
5. Step 5: Solve for x
   x = 1,470,385.30/1,349.31
6. Step 6: Final answer
   x = 1,089.73