Finding the Fourth Proportional to 1,389.89, 1,917.90 and 792.41

Step by Step Solution

1. Step 1: Write the proportion equation
   1,389.89 : 1,917.90 = 792.41 : x
2. Step 2: Convert to fraction form
   1,389.89/1,917.90 = 792.41/x
3. Step 3: Cross multiply
   1,389.89x = 1,917.90 × 792.41
4. Step 4: Simplify right side
   1,389.89x = 1,519,753.55
5. Step 5: Solve for x
   x = 1,519,753.55/1,389.89
6. Step 6: Final answer
   x = 1,093.43