Finding the Fourth Proportional to 139,899.42, 193,013.82 and 85,431.71

Step by Step Solution

1. Step 1: Write the proportion equation
   139,899.42 : 193,013.82 = 85,431.71 : x
2. Step 2: Convert to fraction form
   139,899.42/193,013.82 = 85,431.71/x
3. Step 3: Cross multiply
   139,899.42x = 193,013.82 × 85,431.71
4. Step 4: Simplify right side
   139,899.42x = 16,489,501,178.77
5. Step 5: Solve for x
   x = 16,489,501,178.77/139,899.42
6. Step 6: Final answer
   x = 117,866.83