Finding the Fourth Proportional to 1,356.54, 1,872.70 and 878.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,356.54 : 1,872.70 = 878.56 : x
2. Step 2: Convert to fraction form
   1,356.54/1,872.70 = 878.56/x
3. Step 3: Cross multiply
   1,356.54x = 1,872.70 × 878.56
4. Step 4: Simplify right side
   1,356.54x = 1,645,280.94
5. Step 5: Solve for x
   x = 1,645,280.94/1,356.54
6. Step 6: Final answer
   x = 1,212.85