Finding the Fourth Proportional to 12,402.72, 18,689.34 and 10,259.46

Step by Step Solution

1. Step 1: Write the proportion equation
   12,402.72 : 18,689.34 = 10,259.46 : x
2. Step 2: Convert to fraction form
   12,402.72/18,689.34 = 10,259.46/x
3. Step 3: Cross multiply
   12,402.72x = 18,689.34 × 10,259.46
4. Step 4: Simplify right side
   12,402.72x = 191,742,536.16
5. Step 5: Solve for x
   x = 191,742,536.16/12,402.72
6. Step 6: Final answer
   x = 15,459.72