Finding the Fourth Proportional to 257,648.45, 386,499.17 and 89,168.47

Step by Step Solution

1. Step 1: Write the proportion equation
   257,648.45 : 386,499.17 = 89,168.47 : x
2. Step 2: Convert to fraction form
   257,648.45/386,499.17 = 89,168.47/x
3. Step 3: Cross multiply
   257,648.45x = 386,499.17 × 89,168.47
4. Step 4: Simplify right side
   257,648.45x = 34,463,538,901.84
5. Step 5: Solve for x
   x = 34,463,538,901.84/257,648.45
6. Step 6: Final answer
   x = 133,761.87