Finding the Fourth Proportional to 5,678.45, 7,829.55 and 3,886.79

Step by Step Solution

1. Step 1: Write the proportion equation
   5,678.45 : 7,829.55 = 3,886.79 : x
2. Step 2: Convert to fraction form
   5,678.45/7,829.55 = 3,886.79/x
3. Step 3: Cross multiply
   5,678.45x = 7,829.55 × 3,886.79
4. Step 4: Simplify right side
   5,678.45x = 30,431,836.22
5. Step 5: Solve for x
   x = 30,431,836.22/5,678.45
6. Step 6: Final answer
   x = 5,359.18