Finding the Third Proportional to 12,980 and 20,136

Step by Step Solution

1. Step 1: Write the proportion equation
   12,980 : 20,136 = 20,136 : x
2. Step 2: Convert to fraction form
   12,980/20,136 = 20,136/x
3. Step 3: Cross multiply
   12,980x = 20,136 × 20,136
4. Step 4: Simplify right side
   12,980x = 405,458,496
5. Step 5: Solve for x
   x = 405,458,496/12,980
6. Step 6: Final answer
   x = 31,237.17