Finding the Fourth Proportional to 3,899.76, 5,849.82 and 978.09

Step by Step Solution

1. Step 1: Write the proportion equation
   3,899.76 : 5,849.82 = 978.09 : x
2. Step 2: Convert to fraction form
   3,899.76/5,849.82 = 978.09/x
3. Step 3: Cross multiply
   3,899.76x = 5,849.82 × 978.09
4. Step 4: Simplify right side
   3,899.76x = 5,721,650.44
5. Step 5: Solve for x
   x = 5,721,650.44/3,899.76
6. Step 6: Final answer
   x = 1,467.18