Finding the Third Proportional to 139.13 and 300.38

Step by Step Solution

1. Step 1: Write the proportion equation
   139.13 : 300.38 = 300.38 : x
2. Step 2: Convert to fraction form
   139.13/300.38 = 300.38/x
3. Step 3: Cross multiply
   139.13x = 300.38 × 300.38
4. Step 4: Simplify right side
   139.13x = 90,225.14
5. Step 5: Solve for x
   x = 90,225.14/139.13
6. Step 6: Final answer
   x = 648.52