Finding the Fourth Proportional to 7,043.38, 9,720.15 and 3,899.59

Step by Step Solution

1. Step 1: Write the proportion equation
   7,043.38 : 9,720.15 = 3,899.59 : x
2. Step 2: Convert to fraction form
   7,043.38/9,720.15 = 3,899.59/x
3. Step 3: Cross multiply
   7,043.38x = 9,720.15 × 3,899.59
4. Step 4: Simplify right side
   7,043.38x = 37,904,599.74
5. Step 5: Solve for x
   x = 37,904,599.74/7,043.38
6. Step 6: Final answer
   x = 5,381.59