Finding the Fourth Proportional to 28,522.62, 42,802.56 and 12,940.38

Step by Step Solution

1. Step 1: Write the proportion equation
   28,522.62 : 42,802.56 = 12,940.38 : x
2. Step 2: Convert to fraction form
   28,522.62/42,802.56 = 12,940.38/x
3. Step 3: Cross multiply
   28,522.62x = 42,802.56 × 12,940.38
4. Step 4: Simplify right side
   28,522.62x = 553,881,391.37
5. Step 5: Solve for x
   x = 553,881,391.37/28,522.62
6. Step 6: Final answer
   x = 19,419.02