Finding the Fourth Proportional to 21,187.56, 31,782.86 and 5,605

Step by Step Solution

1. Step 1: Write the proportion equation
   21,187.56 : 31,782.86 = 5,605 : x
2. Step 2: Convert to fraction form
   21,187.56/31,782.86 = 5,605/x
3. Step 3: Cross multiply
   21,187.56x = 31,782.86 × 5,605
4. Step 4: Simplify right side
   21,187.56x = 178,142,930.30
5. Step 5: Solve for x
   x = 178,142,930.30/21,187.56
6. Step 6: Final answer
   x = 8,407.90