Finding the Third Proportional to 21,123 and 28,687.50

Step by Step Solution

1. Step 1: Write the proportion equation
   21,123 : 28,687.50 = 28,687.50 : x
2. Step 2: Convert to fraction form
   21,123/28,687.50 = 28,687.50/x
3. Step 3: Cross multiply
   21,123x = 28,687.50 × 28,687.50
4. Step 4: Simplify right side
   21,123x = 822,972,656.25
5. Step 5: Solve for x
   x = 822,972,656.25/21,123
6. Step 6: Final answer
   x = 38,960.97