Finding the Third Proportional to 55,221.75 and 86,386.50

Step by Step Solution

1. Step 1: Write the proportion equation
   55,221.75 : 86,386.50 = 86,386.50 : x
2. Step 2: Convert to fraction form
   55,221.75/86,386.50 = 86,386.50/x
3. Step 3: Cross multiply
   55,221.75x = 86,386.50 × 86,386.50
4. Step 4: Simplify right side
   55,221.75x = 7,462,627,382.25
5. Step 5: Solve for x
   x = 7,462,627,382.25/55,221.75
6. Step 6: Final answer
   x = 135,139.28