Finding the Fourth Proportional to 5,680.13, 7,839.38 and 5,431.05

Step by Step Solution

1. Step 1: Write the proportion equation
   5,680.13 : 7,839.38 = 5,431.05 : x
2. Step 2: Convert to fraction form
   5,680.13/7,839.38 = 5,431.05/x
3. Step 3: Cross multiply
   5,680.13x = 7,839.38 × 5,431.05
4. Step 4: Simplify right side
   5,680.13x = 42,576,078.33
5. Step 5: Solve for x
   x = 42,576,078.33/5,680.13
6. Step 6: Final answer
   x = 7,495.62