Finding the Fourth Proportional to 3,690.38, 5,494.60 and 3,638.72

Step by Step Solution

1. Step 1: Write the proportion equation
   3,690.38 : 5,494.60 = 3,638.72 : x
2. Step 2: Convert to fraction form
   3,690.38/5,494.60 = 3,638.72/x
3. Step 3: Cross multiply
   3,690.38x = 5,494.60 × 3,638.72
4. Step 4: Simplify right side
   3,690.38x = 19,993,310.91
5. Step 5: Solve for x
   x = 19,993,310.91/3,690.38
6. Step 6: Final answer
   x = 5,417.68