Finding the Fourth Proportional to 21,162.21, 31,588.80 and 19,620.38

Step by Step Solution

1. Step 1: Write the proportion equation
   21,162.21 : 31,588.80 = 19,620.38 : x
2. Step 2: Convert to fraction form
   21,162.21/31,588.80 = 19,620.38/x
3. Step 3: Cross multiply
   21,162.21x = 31,588.80 × 19,620.38
4. Step 4: Simplify right side
   21,162.21x = 619,784,101.80
5. Step 5: Solve for x
   x = 619,784,101.80/21,162.21
6. Step 6: Final answer
   x = 29,287.31