Finding the Fourth Proportional to 21,322.50, 31,942.18 and 12,981.82

Step by Step Solution

1. Step 1: Write the proportion equation
   21,322.50 : 31,942.18 = 12,981.82 : x
2. Step 2: Convert to fraction form
   21,322.50/31,942.18 = 12,981.82/x
3. Step 3: Cross multiply
   21,322.50x = 31,942.18 × 12,981.82
4. Step 4: Simplify right side
   21,322.50x = 414,667,631.17
5. Step 5: Solve for x
   x = 414,667,631.17/21,322.50
6. Step 6: Final answer
   x = 19,447.42