Finding the Third Proportional to 12,891 and 28,131

Step by Step Solution

1. Step 1: Write the proportion equation
   12,891 : 28,131 = 28,131 : x
2. Step 2: Convert to fraction form
   12,891/28,131 = 28,131/x
3. Step 3: Cross multiply
   12,891x = 28,131 × 28,131
4. Step 4: Simplify right side
   12,891x = 791,353,161
5. Step 5: Solve for x
   x = 791,353,161/12,891
6. Step 6: Final answer
   x = 61,388.04