Finding the Fourth Proportional to 1,393.39, 1,922.90 and 763.90

Step by Step Solution

1. Step 1: Write the proportion equation
   1,393.39 : 1,922.90 = 763.90 : x
2. Step 2: Convert to fraction form
   1,393.39/1,922.90 = 763.90/x
3. Step 3: Cross multiply
   1,393.39x = 1,922.90 × 763.90
4. Step 4: Simplify right side
   1,393.39x = 1,468,903.31
5. Step 5: Solve for x
   x = 1,468,903.31/1,393.39
6. Step 6: Final answer
   x = 1,054.19