Finding the Fourth Proportional to 12,787.56, 17,646.78 and 7,122.37

Step by Step Solution

1. Step 1: Write the proportion equation
   12,787.56 : 17,646.78 = 7,122.37 : x
2. Step 2: Convert to fraction form
   12,787.56/17,646.78 = 7,122.37/x
3. Step 3: Cross multiply
   12,787.56x = 17,646.78 × 7,122.37
4. Step 4: Simplify right side
   12,787.56x = 125,686,940.59
5. Step 5: Solve for x
   x = 125,686,940.59/12,787.56
6. Step 6: Final answer
   x = 9,828.85