Finding the Fourth Proportional to 21,823.20, 30,119.94 and 12,870.18

Step by Step Solution

1. Step 1: Write the proportion equation
   21,823.20 : 30,119.94 = 12,870.18 : x
2. Step 2: Convert to fraction form
   21,823.20/30,119.94 = 12,870.18/x
3. Step 3: Cross multiply
   21,823.20x = 30,119.94 × 12,870.18
4. Step 4: Simplify right side
   21,823.20x = 387,649,049.39
5. Step 5: Solve for x
   x = 387,649,049.39/21,823.20
6. Step 6: Final answer
   x = 17,763.16