Finding the Third Proportional to 64,620 and 139,440

Step by Step Solution

1. Step 1: Write the proportion equation
   64,620 : 139,440 = 139,440 : x
2. Step 2: Convert to fraction form
   64,620/139,440 = 139,440/x
3. Step 3: Cross multiply
   64,620x = 139,440 × 139,440
4. Step 4: Simplify right side
   64,620x = 19,443,513,600
5. Step 5: Solve for x
   x = 19,443,513,600/64,620
6. Step 6: Final answer
   x = 300,890.03