Finding the Fourth Proportional to 15,851.39, 21,874.72 and 8,681.23

Step by Step Solution

1. Step 1: Write the proportion equation
   15,851.39 : 21,874.72 = 8,681.23 : x
2. Step 2: Convert to fraction form
   15,851.39/21,874.72 = 8,681.23/x
3. Step 3: Cross multiply
   15,851.39x = 21,874.72 × 8,681.23
4. Step 4: Simplify right side
   15,851.39x = 189,899,475.51
5. Step 5: Solve for x
   x = 189,899,475.51/15,851.39
6. Step 6: Final answer
   x = 11,979.99