Finding the Fourth Proportional to 5,781.82, 7,978.06 and 3,390.89

Step by Step Solution

1. Step 1: Write the proportion equation
   5,781.82 : 7,978.06 = 3,390.89 : x
2. Step 2: Convert to fraction form
   5,781.82/7,978.06 = 3,390.89/x
3. Step 3: Cross multiply
   5,781.82x = 7,978.06 × 3,390.89
4. Step 4: Simplify right side
   5,781.82x = 27,052,768.30
5. Step 5: Solve for x
   x = 27,052,768.30/5,781.82
6. Step 6: Final answer
   x = 4,678.93