Finding the Third Proportional to 12,900 and 28,260

Step by Step Solution

1. Step 1: Write the proportion equation
   12,900 : 28,260 = 28,260 : x
2. Step 2: Convert to fraction form
   12,900/28,260 = 28,260/x
3. Step 3: Cross multiply
   12,900x = 28,260 × 28,260
4. Step 4: Simplify right side
   12,900x = 798,627,600
5. Step 5: Solve for x
   x = 798,627,600/12,900
6. Step 6: Final answer
   x = 61,909.12