Finding the Fourth Proportional to 1,380.88, 1,905.72 and 759.92

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.88 : 1,905.72 = 759.92 : x
2. Step 2: Convert to fraction form
   1,380.88/1,905.72 = 759.92/x
3. Step 3: Cross multiply
   1,380.88x = 1,905.72 × 759.92
4. Step 4: Simplify right side
   1,380.88x = 1,448,194.74
5. Step 5: Solve for x
   x = 1,448,194.74/1,380.88
6. Step 6: Final answer
   x = 1,048.75