Finding the Third Proportional to 64,780 and 139,496

Step by Step Solution

1. Step 1: Write the proportion equation
   64,780 : 139,496 = 139,496 : x
2. Step 2: Convert to fraction form
   64,780/139,496 = 139,496/x
3. Step 3: Cross multiply
   64,780x = 139,496 × 139,496
4. Step 4: Simplify right side
   64,780x = 19,459,134,016
5. Step 5: Solve for x
   x = 19,459,134,016/64,780
6. Step 6: Final answer
   x = 300,387.99