Finding the Fourth Proportional to 1,388.77, 1,916.60 and 799.45

Step by Step Solution

1. Step 1: Write the proportion equation
   1,388.77 : 1,916.60 = 799.45 : x
2. Step 2: Convert to fraction form
   1,388.77/1,916.60 = 799.45/x
3. Step 3: Cross multiply
   1,388.77x = 1,916.60 × 799.45
4. Step 4: Simplify right side
   1,388.77x = 1,532,221.87
5. Step 5: Solve for x
   x = 1,532,221.87/1,388.77
6. Step 6: Final answer
   x = 1,103.29