Finding the Third Proportional to 8,628.19 and 12,820.78

Step by Step Solution

1. Step 1: Write the proportion equation
   8,628.19 : 12,820.78 = 12,820.78 : x
2. Step 2: Convert to fraction form
   8,628.19/12,820.78 = 12,820.78/x
3. Step 3: Cross multiply
   8,628.19x = 12,820.78 × 12,820.78
4. Step 4: Simplify right side
   8,628.19x = 164,372,431.86
5. Step 5: Solve for x
   x = 164,372,431.86/8,628.19
6. Step 6: Final answer
   x = 19,050.63