Finding the Third Proportional to 12,639.38 and 19,657.69

Step by Step Solution

1. Step 1: Write the proportion equation
   12,639.38 : 19,657.69 = 19,657.69 : x
2. Step 2: Convert to fraction form
   12,639.38/19,657.69 = 19,657.69/x
3. Step 3: Cross multiply
   12,639.38x = 19,657.69 × 19,657.69
4. Step 4: Simplify right side
   12,639.38x = 386,424,677.85
5. Step 5: Solve for x
   x = 386,424,677.85/12,639.38
6. Step 6: Final answer
   x = 30,573.08