Finding the Third Proportional to 138,519 and 298,408.50

Step by Step Solution

1. Step 1: Write the proportion equation
   138,519 : 298,408.50 = 298,408.50 : x
2. Step 2: Convert to fraction form
   138,519/298,408.50 = 298,408.50/x
3. Step 3: Cross multiply
   138,519x = 298,408.50 × 298,408.50
4. Step 4: Simplify right side
   138,519x = 89,047,632,872.25
5. Step 5: Solve for x
   x = 89,047,632,872.25/138,519
6. Step 6: Final answer
   x = 642,855.01