Finding the Third Proportional to 138,495 and 210,658.50

Step by Step Solution

1. Step 1: Write the proportion equation
   138,495 : 210,658.50 = 210,658.50 : x
2. Step 2: Convert to fraction form
   138,495/210,658.50 = 210,658.50/x
3. Step 3: Cross multiply
   138,495x = 210,658.50 × 210,658.50
4. Step 4: Simplify right side
   138,495x = 44,377,003,622.25
5. Step 5: Solve for x
   x = 44,377,003,622.25/138,495
6. Step 6: Final answer
   x = 320,423.15