Finding the Fourth Proportional to 1,380.65, 1,903.13 and 937.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.65 : 1,903.13 = 937.78 : x
2. Step 2: Convert to fraction form
   1,380.65/1,903.13 = 937.78/x
3. Step 3: Cross multiply
   1,380.65x = 1,903.13 × 937.78
4. Step 4: Simplify right side
   1,380.65x = 1,784,711.32
5. Step 5: Solve for x
   x = 1,784,711.32/1,380.65
6. Step 6: Final answer
   x = 1,292.66