Finding the Third Proportional to 139.38 and 206.94

Step by Step Solution

1. Step 1: Write the proportion equation
   139.38 : 206.94 = 206.94 : x
2. Step 2: Convert to fraction form
   139.38/206.94 = 206.94/x
3. Step 3: Cross multiply
   139.38x = 206.94 × 206.94
4. Step 4: Simplify right side
   139.38x = 42,823.13
5. Step 5: Solve for x
   x = 42,823.13/139.38
6. Step 6: Final answer
   x = 307.25