Finding the Third Proportional to 65,120 and 139,456

Step by Step Solution

1. Step 1: Write the proportion equation
   65,120 : 139,456 = 139,456 : x
2. Step 2: Convert to fraction form
   65,120/139,456 = 139,456/x
3. Step 3: Cross multiply
   65,120x = 139,456 × 139,456
4. Step 4: Simplify right side
   65,120x = 19,447,975,936
5. Step 5: Solve for x
   x = 19,447,975,936/65,120
6. Step 6: Final answer
   x = 298,648.28