Finding the Fourth Proportional to 21,822.84, 30,114.18 and 12,870.72

Step by Step Solution

1. Step 1: Write the proportion equation
   21,822.84 : 30,114.18 = 12,870.72 : x
2. Step 2: Convert to fraction form
   21,822.84/30,114.18 = 12,870.72/x
3. Step 3: Cross multiply
   21,822.84x = 30,114.18 × 12,870.72
4. Step 4: Simplify right side
   21,822.84x = 387,591,178.81
5. Step 5: Solve for x
   x = 387,591,178.81/21,822.84
6. Step 6: Final answer
   x = 17,760.80