Finding the Fourth Proportional to 260,411.37, 390,648.30 and 91,896.90

Step by Step Solution

1. Step 1: Write the proportion equation
   260,411.37 : 390,648.30 = 91,896.90 : x
2. Step 2: Convert to fraction form
   260,411.37/390,648.30 = 91,896.90/x
3. Step 3: Cross multiply
   260,411.37x = 390,648.30 × 91,896.90
4. Step 4: Simplify right side
   260,411.37x = 35,899,367,760.27
5. Step 5: Solve for x
   x = 35,899,367,760.27/260,411.37
6. Step 6: Final answer
   x = 137,856.38