Finding the Fourth Proportional to 1,393.40, 1,922.81 and 763.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,393.40 : 1,922.81 = 763.80 : x
2. Step 2: Convert to fraction form
   1,393.40/1,922.81 = 763.80/x
3. Step 3: Cross multiply
   1,393.40x = 1,922.81 × 763.80
4. Step 4: Simplify right side
   1,393.40x = 1,468,638.46
5. Step 5: Solve for x
   x = 1,468,638.46/1,393.40
6. Step 6: Final answer
   x = 1,054.00