Finding the Fourth Proportional to 1,978.48, 2,730.41 and 1,139.19

Step by Step Solution

1. Step 1: Write the proportion equation
   1,978.48 : 2,730.41 = 1,139.19 : x
2. Step 2: Convert to fraction form
   1,978.48/2,730.41 = 1,139.19/x
3. Step 3: Cross multiply
   1,978.48x = 2,730.41 × 1,139.19
4. Step 4: Simplify right side
   1,978.48x = 3,110,455.77
5. Step 5: Solve for x
   x = 3,110,455.77/1,978.48
6. Step 6: Final answer
   x = 1,572.14