Finding the Fourth Proportional to 139,148.72, 208,633.56 and 91,708.56

Step by Step Solution

1. Step 1: Write the proportion equation
   139,148.72 : 208,633.56 = 91,708.56 : x
2. Step 2: Convert to fraction form
   139,148.72/208,633.56 = 91,708.56/x
3. Step 3: Cross multiply
   139,148.72x = 208,633.56 × 91,708.56
4. Step 4: Simplify right side
   139,148.72x = 19,133,483,355.27
5. Step 5: Solve for x
   x = 19,133,483,355.27/139,148.72
6. Step 6: Final answer
   x = 137,503.84