Finding the Third Proportional to 64,985.25 and 139,640.25

Step by Step Solution

1. Step 1: Write the proportion equation
   64,985.25 : 139,640.25 = 139,640.25 : x
2. Step 2: Convert to fraction form
   64,985.25/139,640.25 = 139,640.25/x
3. Step 3: Cross multiply
   64,985.25x = 139,640.25 × 139,640.25
4. Step 4: Simplify right side
   64,985.25x = 19,499,399,420.06
5. Step 5: Solve for x
   x = 19,499,399,420.06/64,985.25
6. Step 6: Final answer
   x = 300,058.85