Finding the Fourth Proportional to 139.30, 208.86 and 47.98

Step by Step Solution

1. Step 1: Write the proportion equation
   139.30 : 208.86 = 47.98 : x
2. Step 2: Convert to fraction form
   139.30/208.86 = 47.98/x
3. Step 3: Cross multiply
   139.30x = 208.86 × 47.98
4. Step 4: Simplify right side
   139.30x = 10,021.10
5. Step 5: Solve for x
   x = 10,021.10/139.30
6. Step 6: Final answer
   x = 71.94