Finding the Third Proportional to 81,090 and 129,541.50

Step by Step Solution

1. Step 1: Write the proportion equation
   81,090 : 129,541.50 = 129,541.50 : x
2. Step 2: Convert to fraction form
   81,090/129,541.50 = 129,541.50/x
3. Step 3: Cross multiply
   81,090x = 129,541.50 × 129,541.50
4. Step 4: Simplify right side
   81,090x = 16,781,000,222.25
5. Step 5: Solve for x
   x = 16,781,000,222.25/81,090
6. Step 6: Final answer
   x = 206,942.91