Finding the Third Proportional to 8,355 and 12,787.50

Step by Step Solution

1. Step 1: Write the proportion equation
   8,355 : 12,787.50 = 12,787.50 : x
2. Step 2: Convert to fraction form
   8,355/12,787.50 = 12,787.50/x
3. Step 3: Cross multiply
   8,355x = 12,787.50 × 12,787.50
4. Step 4: Simplify right side
   8,355x = 163,520,156.25
5. Step 5: Solve for x
   x = 163,520,156.25/8,355
6. Step 6: Final answer
   x = 19,571.53