Finding the Third Proportional to 12,872 and 20,174

Step by Step Solution

1. Step 1: Write the proportion equation
   12,872 : 20,174 = 20,174 : x
2. Step 2: Convert to fraction form
   12,872/20,174 = 20,174/x
3. Step 3: Cross multiply
   12,872x = 20,174 × 20,174
4. Step 4: Simplify right side
   12,872x = 406,990,276
5. Step 5: Solve for x
   x = 406,990,276/12,872
6. Step 6: Final answer
   x = 31,618.26