Finding the Fourth Proportional to 1,405.89, 1,939.68 and 908.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.89 : 1,939.68 = 908.69 : x
2. Step 2: Convert to fraction form
   1,405.89/1,939.68 = 908.69/x
3. Step 3: Cross multiply
   1,405.89x = 1,939.68 × 908.69
4. Step 4: Simplify right side
   1,405.89x = 1,762,558.12
5. Step 5: Solve for x
   x = 1,762,558.12/1,405.89
6. Step 6: Final answer
   x = 1,253.70