Finding the Fourth Proportional to 1,389.05, 1,916.93 and 799.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,389.05 : 1,916.93 = 799.61 : x
2. Step 2: Convert to fraction form
   1,389.05/1,916.93 = 799.61/x
3. Step 3: Cross multiply
   1,389.05x = 1,916.93 × 799.61
4. Step 4: Simplify right side
   1,389.05x = 1,532,792.40
5. Step 5: Solve for x
   x = 1,532,792.40/1,389.05
6. Step 6: Final answer
   x = 1,103.48