Finding the Third Proportional to 64,879.88 and 139,459.50

Step by Step Solution

1. Step 1: Write the proportion equation
   64,879.88 : 139,459.50 = 139,459.50 : x
2. Step 2: Convert to fraction form
   64,879.88/139,459.50 = 139,459.50/x
3. Step 3: Cross multiply
   64,879.88x = 139,459.50 × 139,459.50
4. Step 4: Simplify right side
   64,879.88x = 19,448,952,140.25
5. Step 5: Solve for x
   x = 19,448,952,140.25/64,879.88
6. Step 6: Final answer
   x = 299,768.64