Finding the Third Proportional to 12,819.94 and 19,678.78

Step by Step Solution

1. Step 1: Write the proportion equation
   12,819.94 : 19,678.78 = 19,678.78 : x
2. Step 2: Convert to fraction form
   12,819.94/19,678.78 = 19,678.78/x
3. Step 3: Cross multiply
   12,819.94x = 19,678.78 × 19,678.78
4. Step 4: Simplify right side
   12,819.94x = 387,254,431.49
5. Step 5: Solve for x
   x = 387,254,431.49/12,819.94
6. Step 6: Final answer
   x = 30,207.20