Finding the Fourth Proportional to 2,012.96, 2,777.61 and 1,128.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,012.96 : 2,777.61 = 1,128.78 : x
2. Step 2: Convert to fraction form
   2,012.96/2,777.61 = 1,128.78/x
3. Step 3: Cross multiply
   2,012.96x = 2,777.61 × 1,128.78
4. Step 4: Simplify right side
   2,012.96x = 3,135,310.62
5. Step 5: Solve for x
   x = 3,135,310.62/2,012.96
6. Step 6: Final answer
   x = 1,557.56