Finding the Third Proportional to 70,128.50 and 98,640.75

Step by Step Solution

1. Step 1: Write the proportion equation
   70,128.50 : 98,640.75 = 98,640.75 : x
2. Step 2: Convert to fraction form
   70,128.50/98,640.75 = 98,640.75/x
3. Step 3: Cross multiply
   70,128.50x = 98,640.75 × 98,640.75
4. Step 4: Simplify right side
   70,128.50x = 9,729,997,560.56
5. Step 5: Solve for x
   x = 9,729,997,560.56/70,128.50
6. Step 6: Final answer
   x = 138,745.27