Finding the Third Proportional to 12,400 and 19,760

Step by Step Solution

1. Step 1: Write the proportion equation
   12,400 : 19,760 = 19,760 : x
2. Step 2: Convert to fraction form
   12,400/19,760 = 19,760/x
3. Step 3: Cross multiply
   12,400x = 19,760 × 19,760
4. Step 4: Simplify right side
   12,400x = 390,457,600
5. Step 5: Solve for x
   x = 390,457,600/12,400
6. Step 6: Final answer
   x = 31,488.52