Finding the Fourth Proportional to 21,786.76, 30,066.15 and 12,355.12

Step by Step Solution

1. Step 1: Write the proportion equation
   21,786.76 : 30,066.15 = 12,355.12 : x
2. Step 2: Convert to fraction form
   21,786.76/30,066.15 = 12,355.12/x
3. Step 3: Cross multiply
   21,786.76x = 30,066.15 × 12,355.12
4. Step 4: Simplify right side
   21,786.76x = 371,470,891.19
5. Step 5: Solve for x
   x = 371,470,891.19/21,786.76
6. Step 6: Final answer
   x = 17,050.30