Finding the Third Proportional to 12,139.88 and 15,982.31

Step by Step Solution

1. Step 1: Write the proportion equation
   12,139.88 : 15,982.31 = 15,982.31 : x
2. Step 2: Convert to fraction form
   12,139.88/15,982.31 = 15,982.31/x
3. Step 3: Cross multiply
   12,139.88x = 15,982.31 × 15,982.31
4. Step 4: Simplify right side
   12,139.88x = 255,434,312.85
5. Step 5: Solve for x
   x = 255,434,312.85/12,139.88
6. Step 6: Final answer
   x = 21,040.93