Finding the Third Proportional to 2,558 and 5,521

Step by Step Solution

1. Step 1: Write the proportion equation
   2,558 : 5,521 = 5,521 : x
2. Step 2: Convert to fraction form
   2,558/5,521 = 5,521/x
3. Step 3: Cross multiply
   2,558x = 5,521 × 5,521
4. Step 4: Simplify right side
   2,558x = 30,481,441
5. Step 5: Solve for x
   x = 30,481,441/2,558
6. Step 6: Final answer
   x = 11,916.12