Finding the Fourth Proportional to 21,151.33, 31,719.70 and 8,667.81

Step by Step Solution

1. Step 1: Write the proportion equation
   21,151.33 : 31,719.70 = 8,667.81 : x
2. Step 2: Convert to fraction form
   21,151.33/31,719.70 = 8,667.81/x
3. Step 3: Cross multiply
   21,151.33x = 31,719.70 × 8,667.81
4. Step 4: Simplify right side
   21,151.33x = 274,940,343.69
5. Step 5: Solve for x
   x = 274,940,343.69/21,151.33
6. Step 6: Final answer
   x = 12,998.73