Finding the Third Proportional to 12,400 and 18,890

Step by Step Solution

1. Step 1: Write the proportion equation
   12,400 : 18,890 = 18,890 : x
2. Step 2: Convert to fraction form
   12,400/18,890 = 18,890/x
3. Step 3: Cross multiply
   12,400x = 18,890 × 18,890
4. Step 4: Simplify right side
   12,400x = 356,832,100
5. Step 5: Solve for x
   x = 356,832,100/12,400
6. Step 6: Final answer
   x = 28,776.78