Finding the Third Proportional to 81,340 and 129,870

Step by Step Solution

1. Step 1: Write the proportion equation
   81,340 : 129,870 = 129,870 : x
2. Step 2: Convert to fraction form
   81,340/129,870 = 129,870/x
3. Step 3: Cross multiply
   81,340x = 129,870 × 129,870
4. Step 4: Simplify right side
   81,340x = 16,866,216,900
5. Step 5: Solve for x
   x = 16,866,216,900/81,340
6. Step 6: Final answer
   x = 207,354.52