Finding the Third Proportional to 21,511 and 28,905

Step by Step Solution

1. Step 1: Write the proportion equation
   21,511 : 28,905 = 28,905 : x
2. Step 2: Convert to fraction form
   21,511/28,905 = 28,905/x
3. Step 3: Cross multiply
   21,511x = 28,905 × 28,905
4. Step 4: Simplify right side
   21,511x = 835,499,025
5. Step 5: Solve for x
   x = 835,499,025/21,511
6. Step 6: Final answer
   x = 38,840.55