Finding the Third Proportional to 12,387.94 and 15,121.69

Step by Step Solution

1. Step 1: Write the proportion equation
   12,387.94 : 15,121.69 = 15,121.69 : x
2. Step 2: Convert to fraction form
   12,387.94/15,121.69 = 15,121.69/x
3. Step 3: Cross multiply
   12,387.94x = 15,121.69 × 15,121.69
4. Step 4: Simplify right side
   12,387.94x = 228,665,432.85
5. Step 5: Solve for x
   x = 228,665,432.85/12,387.94
6. Step 6: Final answer
   x = 18,458.72