Finding the Fourth Proportional to 13,499.39, 20,249.56 and 3,638.91

Step by Step Solution

1. Step 1: Write the proportion equation
   13,499.39 : 20,249.56 = 3,638.91 : x
2. Step 2: Convert to fraction form
   13,499.39/20,249.56 = 3,638.91/x
3. Step 3: Cross multiply
   13,499.39x = 20,249.56 × 3,638.91
4. Step 4: Simplify right side
   13,499.39x = 73,686,326.38
5. Step 5: Solve for x
   x = 73,686,326.38/13,499.39
6. Step 6: Final answer
   x = 5,458.49