Finding the Third Proportional to 10,818 and 18,121.50

Step by Step Solution

1. Step 1: Write the proportion equation
   10,818 : 18,121.50 = 18,121.50 : x
2. Step 2: Convert to fraction form
   10,818/18,121.50 = 18,121.50/x
3. Step 3: Cross multiply
   10,818x = 18,121.50 × 18,121.50
4. Step 4: Simplify right side
   10,818x = 328,388,762.25
5. Step 5: Solve for x
   x = 328,388,762.25/10,818
6. Step 6: Final answer
   x = 30,355.77