Finding the Fourth Proportional to 28,339.93, 42,513.83 and 12,543.71

Step by Step Solution

1. Step 1: Write the proportion equation
   28,339.93 : 42,513.83 = 12,543.71 : x
2. Step 2: Convert to fraction form
   28,339.93/42,513.83 = 12,543.71/x
3. Step 3: Cross multiply
   28,339.93x = 42,513.83 × 12,543.71
4. Step 4: Simplify right side
   28,339.93x = 533,281,154.51
5. Step 5: Solve for x
   x = 533,281,154.51/28,339.93
6. Step 6: Final answer
   x = 18,817.31