Finding the Fourth Proportional to 259,774.28, 389,683.52 and 91,280.06

Step by Step Solution

1. Step 1: Write the proportion equation
   259,774.28 : 389,683.52 = 91,280.06 : x
2. Step 2: Convert to fraction form
   259,774.28/389,683.52 = 91,280.06/x
3. Step 3: Cross multiply
   259,774.28x = 389,683.52 × 91,280.06
4. Step 4: Simplify right side
   259,774.28x = 35,570,334,998.86
5. Step 5: Solve for x
   x = 35,570,334,998.86/259,774.28
6. Step 6: Final answer
   x = 136,927.85