Finding the Third Proportional to 139.75 and 298.63

Step by Step Solution

1. Step 1: Write the proportion equation
   139.75 : 298.63 = 298.63 : x
2. Step 2: Convert to fraction form
   139.75/298.63 = 298.63/x
3. Step 3: Cross multiply
   139.75x = 298.63 × 298.63
4. Step 4: Simplify right side
   139.75x = 89,176.89
5. Step 5: Solve for x
   x = 89,176.89/139.75
6. Step 6: Final answer
   x = 638.12