Finding the Third Proportional to 98,638 and 139,570

Step by Step Solution

1. Step 1: Write the proportion equation
   98,638 : 139,570 = 139,570 : x
2. Step 2: Convert to fraction form
   98,638/139,570 = 139,570/x
3. Step 3: Cross multiply
   98,638x = 139,570 × 139,570
4. Step 4: Simplify right side
   98,638x = 19,479,784,900
5. Step 5: Solve for x
   x = 19,479,784,900/98,638
6. Step 6: Final answer
   x = 197,487.63