Finding the Third Proportional to 12,291.75 and 18,688.50

Step by Step Solution

1. Step 1: Write the proportion equation
   12,291.75 : 18,688.50 = 18,688.50 : x
2. Step 2: Convert to fraction form
   12,291.75/18,688.50 = 18,688.50/x
3. Step 3: Cross multiply
   12,291.75x = 18,688.50 × 18,688.50
4. Step 4: Simplify right side
   12,291.75x = 349,260,032.25
5. Step 5: Solve for x
   x = 349,260,032.25/12,291.75
6. Step 6: Final answer
   x = 28,414.18