Finding the Fourth Proportional to 1,380.72, 1,904.14 and 908.45

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.72 : 1,904.14 = 908.45 : x
2. Step 2: Convert to fraction form
   1,380.72/1,904.14 = 908.45/x
3. Step 3: Cross multiply
   1,380.72x = 1,904.14 × 908.45
4. Step 4: Simplify right side
   1,380.72x = 1,729,814.74
5. Step 5: Solve for x
   x = 1,729,814.74/1,380.72
6. Step 6: Final answer
   x = 1,252.83