Finding the Third Proportional to 139.50 and 300.75

Step by Step Solution

1. Step 1: Write the proportion equation
   139.50 : 300.75 = 300.75 : x
2. Step 2: Convert to fraction form
   139.50/300.75 = 300.75/x
3. Step 3: Cross multiply
   139.50x = 300.75 × 300.75
4. Step 4: Simplify right side
   139.50x = 90,450.56
5. Step 5: Solve for x
   x = 90,450.56/139.50
6. Step 6: Final answer
   x = 648.39