Finding the Fourth Proportional to 263,626.72, 395,461.76 and 86,129.76

Step by Step Solution

1. Step 1: Write the proportion equation
   263,626.72 : 395,461.76 = 86,129.76 : x
2. Step 2: Convert to fraction form
   263,626.72/395,461.76 = 86,129.76/x
3. Step 3: Cross multiply
   263,626.72x = 395,461.76 × 86,129.76
4. Step 4: Simplify right side
   263,626.72x = 34,061,026,477.98
5. Step 5: Solve for x
   x = 34,061,026,477.98/263,626.72
6. Step 6: Final answer
   x = 129,201.72