Finding the Fourth Proportional to 3,978.89, 5,968.62 and 1,057.13

Step by Step Solution

1. Step 1: Write the proportion equation
   3,978.89 : 5,968.62 = 1,057.13 : x
2. Step 2: Convert to fraction form
   3,978.89/5,968.62 = 1,057.13/x
3. Step 3: Cross multiply
   3,978.89x = 5,968.62 × 1,057.13
4. Step 4: Simplify right side
   3,978.89x = 6,309,607.26
5. Step 5: Solve for x
   x = 6,309,607.26/3,978.89
6. Step 6: Final answer
   x = 1,585.77