Finding the Fourth Proportional to 2,015.20, 2,780.98 and 1,131

Step by Step Solution

1. Step 1: Write the proportion equation
   2,015.20 : 2,780.98 = 1,131 : x
2. Step 2: Convert to fraction form
   2,015.20/2,780.98 = 1,131/x
3. Step 3: Cross multiply
   2,015.20x = 2,780.98 × 1,131
4. Step 4: Simplify right side
   2,015.20x = 3,145,288.38
5. Step 5: Solve for x
   x = 3,145,288.38/2,015.20
6. Step 6: Final answer
   x = 1,560.78