Finding the Fourth Proportional to 21,772.55, 30,047.31 and 12,215.47

Step by Step Solution

1. Step 1: Write the proportion equation
   21,772.55 : 30,047.31 = 12,215.47 : x
2. Step 2: Convert to fraction form
   21,772.55/30,047.31 = 12,215.47/x
3. Step 3: Cross multiply
   21,772.55x = 30,047.31 × 12,215.47
4. Step 4: Simplify right side
   21,772.55x = 367,041,863.65
5. Step 5: Solve for x
   x = 367,041,863.65/21,772.55
6. Step 6: Final answer
   x = 16,858.01