Finding the Fourth Proportional to 1,978.12, 2,729.75 and 1,138.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,978.12 : 2,729.75 = 1,138.83 : x
2. Step 2: Convert to fraction form
   1,978.12/2,729.75 = 1,138.83/x
3. Step 3: Cross multiply
   1,978.12x = 2,729.75 × 1,138.83
4. Step 4: Simplify right side
   1,978.12x = 3,108,734.70
5. Step 5: Solve for x
   x = 3,108,734.70/1,978.12
6. Step 6: Final answer
   x = 1,571.56