Finding the Third Proportional to 64,702.50 and 139,239

Step by Step Solution

1. Step 1: Write the proportion equation
   64,702.50 : 139,239 = 139,239 : x
2. Step 2: Convert to fraction form
   64,702.50/139,239 = 139,239/x
3. Step 3: Cross multiply
   64,702.50x = 139,239 × 139,239
4. Step 4: Simplify right side
   64,702.50x = 19,387,499,121
5. Step 5: Solve for x
   x = 19,387,499,121/64,702.50
6. Step 6: Final answer
   x = 299,640.65