Finding the Third Proportional to 139.31 and 304.31

Step by Step Solution

1. Step 1: Write the proportion equation
   139.31 : 304.31 = 304.31 : x
2. Step 2: Convert to fraction form
   139.31/304.31 = 304.31/x
3. Step 3: Cross multiply
   139.31x = 304.31 × 304.31
4. Step 4: Simplify right side
   139.31x = 92,606.10
5. Step 5: Solve for x
   x = 92,606.10/139.31
6. Step 6: Final answer
   x = 664.74