Finding the Fourth Proportional to 2,111.20, 2,913 and 1,226.55

Step by Step Solution

1. Step 1: Write the proportion equation
   2,111.20 : 2,913 = 1,226.55 : x
2. Step 2: Convert to fraction form
   2,111.20/2,913 = 1,226.55/x
3. Step 3: Cross multiply
   2,111.20x = 2,913 × 1,226.55
4. Step 4: Simplify right side
   2,111.20x = 3,572,940.15
5. Step 5: Solve for x
   x = 3,572,940.15/2,111.20
6. Step 6: Final answer
   x = 1,692.37