Finding the Fourth Proportional to 1,382.46, 1,907.76 and 909.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,382.46 : 1,907.76 = 909.78 : x
2. Step 2: Convert to fraction form
   1,382.46/1,907.76 = 909.78/x
3. Step 3: Cross multiply
   1,382.46x = 1,907.76 × 909.78
4. Step 4: Simplify right side
   1,382.46x = 1,735,641.89
5. Step 5: Solve for x
   x = 1,735,641.89/1,382.46
6. Step 6: Final answer
   x = 1,255.47