Finding the Fourth Proportional to 12,748.31, 19,115.90 and 5,722.31

Step by Step Solution

1. Step 1: Write the proportion equation
   12,748.31 : 19,115.90 = 5,722.31 : x
2. Step 2: Convert to fraction form
   12,748.31/19,115.90 = 5,722.31/x
3. Step 3: Cross multiply
   12,748.31x = 19,115.90 × 5,722.31
4. Step 4: Simplify right side
   12,748.31x = 109,387,065.72
5. Step 5: Solve for x
   x = 109,387,065.72/12,748.31
6. Step 6: Final answer
   x = 8,580.51