Finding the Fourth Proportional to 1,381.89, 1,907.10 and 909.93

Step by Step Solution

1. Step 1: Write the proportion equation
   1,381.89 : 1,907.10 = 909.93 : x
2. Step 2: Convert to fraction form
   1,381.89/1,907.10 = 909.93/x
3. Step 3: Cross multiply
   1,381.89x = 1,907.10 × 909.93
4. Step 4: Simplify right side
   1,381.89x = 1,735,327.50
5. Step 5: Solve for x
   x = 1,735,327.50/1,381.89
6. Step 6: Final answer
   x = 1,255.76