Finding the Fourth Proportional to 21,046.18, 31,547.31 and 8,561.20

Step by Step Solution

1. Step 1: Write the proportion equation
   21,046.18 : 31,547.31 = 8,561.20 : x
2. Step 2: Convert to fraction form
   21,046.18/31,547.31 = 8,561.20/x
3. Step 3: Cross multiply
   21,046.18x = 31,547.31 × 8,561.20
4. Step 4: Simplify right side
   21,046.18x = 270,082,830.37
5. Step 5: Solve for x
   x = 270,082,830.37/21,046.18
6. Step 6: Final answer
   x = 12,832.87