Finding the Third Proportional to 53,968.78 and 86,661.56

Step by Step Solution

1. Step 1: Write the proportion equation
   53,968.78 : 86,661.56 = 86,661.56 : x
2. Step 2: Convert to fraction form
   53,968.78/86,661.56 = 86,661.56/x
3. Step 3: Cross multiply
   53,968.78x = 86,661.56 × 86,661.56
4. Step 4: Simplify right side
   53,968.78x = 7,510,226,414.94
5. Step 5: Solve for x
   x = 7,510,226,414.94/53,968.78
6. Step 6: Final answer
   x = 139,158.72