Finding the Fourth Proportional to 1,381.68, 1,906.20 and 1,066.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,381.68 : 1,906.20 = 1,066.39 : x
2. Step 2: Convert to fraction form
   1,381.68/1,906.20 = 1,066.39/x
3. Step 3: Cross multiply
   1,381.68x = 1,906.20 × 1,066.39
4. Step 4: Simplify right side
   1,381.68x = 2,032,747.85
5. Step 5: Solve for x
   x = 2,032,747.85/1,381.68
6. Step 6: Final answer
   x = 1,471.21