Finding the Fourth Proportional to 20,754.78, 31,141.89 and 12,959.34

Step by Step Solution

1. Step 1: Write the proportion equation
   20,754.78 : 31,141.89 = 12,959.34 : x
2. Step 2: Convert to fraction form
   20,754.78/31,141.89 = 12,959.34/x
3. Step 3: Cross multiply
   20,754.78x = 31,141.89 × 12,959.34
4. Step 4: Simplify right side
   20,754.78x = 403,578,340.75
5. Step 5: Solve for x
   x = 403,578,340.75/20,754.78
6. Step 6: Final answer
   x = 19,445.08