Finding the Fourth Proportional to 28,629.50, 42,957.81 and 13,830.12

Step by Step Solution

1. Step 1: Write the proportion equation
   28,629.50 : 42,957.81 = 13,830.12 : x
2. Step 2: Convert to fraction form
   28,629.50/42,957.81 = 13,830.12/x
3. Step 3: Cross multiply
   28,629.50x = 42,957.81 × 13,830.12
4. Step 4: Simplify right side
   28,629.50x = 594,111,667.24
5. Step 5: Solve for x
   x = 594,111,667.24/28,629.50
6. Step 6: Final answer
   x = 20,751.73