Finding the Fourth Proportional to 2,012.31, 2,776.86 and 1,128.11

Step by Step Solution

1. Step 1: Write the proportion equation
   2,012.31 : 2,776.86 = 1,128.11 : x
2. Step 2: Convert to fraction form
   2,012.31/2,776.86 = 1,128.11/x
3. Step 3: Cross multiply
   2,012.31x = 2,776.86 × 1,128.11
4. Step 4: Simplify right side
   2,012.31x = 3,132,603.53
5. Step 5: Solve for x
   x = 3,132,603.53/2,012.31
6. Step 6: Final answer
   x = 1,556.72