Finding the Fourth Proportional to 1,380.78, 2,067.53 and 1,206.63

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.78 : 2,067.53 = 1,206.63 : x
2. Step 2: Convert to fraction form
   1,380.78/2,067.53 = 1,206.63/x
3. Step 3: Cross multiply
   1,380.78x = 2,067.53 × 1,206.63
4. Step 4: Simplify right side
   1,380.78x = 2,494,737.69
5. Step 5: Solve for x
   x = 2,494,737.69/1,380.78
6. Step 6: Final answer
   x = 1,806.76