Finding the Fourth Proportional to 139.31, 192.18 and 97.86

Step by Step Solution

1. Step 1: Write the proportion equation
   139.31 : 192.18 = 97.86 : x
2. Step 2: Convert to fraction form
   139.31/192.18 = 97.86/x
3. Step 3: Cross multiply
   139.31x = 192.18 × 97.86
4. Step 4: Simplify right side
   139.31x = 18,806.73
5. Step 5: Solve for x
   x = 18,806.73/139.31
6. Step 6: Final answer
   x = 135.00