Finding the Fourth Proportional to 2,978.31, 4,466.85 and 1,128.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,978.31 : 4,466.85 = 1,128.78 : x
2. Step 2: Convert to fraction form
   2,978.31/4,466.85 = 1,128.78/x
3. Step 3: Cross multiply
   2,978.31x = 4,466.85 × 1,128.78
4. Step 4: Simplify right side
   2,978.31x = 5,042,102.11
5. Step 5: Solve for x
   x = 5,042,102.11/2,978.31
6. Step 6: Final answer
   x = 1,692.94