Finding the Fourth Proportional to 21,196.95, 31,800.42 and 6,405.99

Step by Step Solution

1. Step 1: Write the proportion equation
   21,196.95 : 31,800.42 = 6,405.99 : x
2. Step 2: Convert to fraction form
   21,196.95/31,800.42 = 6,405.99/x
3. Step 3: Cross multiply
   21,196.95x = 31,800.42 × 6,405.99
4. Step 4: Simplify right side
   21,196.95x = 203,713,172.52
5. Step 5: Solve for x
   x = 203,713,172.52/21,196.95
6. Step 6: Final answer
   x = 9,610.49