Finding the Fourth Proportional to 2,576.15, 3,555.05 and 1,397.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,576.15 : 3,555.05 = 1,397.20 : x
2. Step 2: Convert to fraction form
   2,576.15/3,555.05 = 1,397.20/x
3. Step 3: Cross multiply
   2,576.15x = 3,555.05 × 1,397.20
4. Step 4: Simplify right side
   2,576.15x = 4,967,115.86
5. Step 5: Solve for x
   x = 4,967,115.86/2,576.15
6. Step 6: Final answer
   x = 1,928.12