Finding the Fourth Proportional to 21,224.34, 31,680.71 and 19,660.50

Step by Step Solution

1. Step 1: Write the proportion equation
   21,224.34 : 31,680.71 = 19,660.50 : x
2. Step 2: Convert to fraction form
   21,224.34/31,680.71 = 19,660.50/x
3. Step 3: Cross multiply
   21,224.34x = 31,680.71 × 19,660.50
4. Step 4: Simplify right side
   21,224.34x = 622,858,500.65
5. Step 5: Solve for x
   x = 622,858,500.65/21,224.34
6. Step 6: Final answer
   x = 29,346.42