Finding the Fourth Proportional to 139,267.42, 208,697.01 and 86,516.98

Step by Step Solution

1. Step 1: Write the proportion equation
   139,267.42 : 208,697.01 = 86,516.98 : x
2. Step 2: Convert to fraction form
   139,267.42/208,697.01 = 86,516.98/x
3. Step 3: Cross multiply
   139,267.42x = 208,697.01 × 86,516.98
4. Step 4: Simplify right side
   139,267.42x = 18,055,835,040.23
5. Step 5: Solve for x
   x = 18,055,835,040.23/139,267.42
6. Step 6: Final answer
   x = 129,648.66