Finding the Fourth Proportional to 28,208.27, 42,312.71 and 13,418.69

Step by Step Solution

1. Step 1: Write the proportion equation
   28,208.27 : 42,312.71 = 13,418.69 : x
2. Step 2: Convert to fraction form
   28,208.27/42,312.71 = 13,418.69/x
3. Step 3: Cross multiply
   28,208.27x = 42,312.71 × 13,418.69
4. Step 4: Simplify right side
   28,208.27x = 567,781,138.55
5. Step 5: Solve for x
   x = 567,781,138.55/28,208.27
6. Step 6: Final answer
   x = 20,128.18