Finding the Fourth Proportional to 2,311.90, 3,468.72 and 1,388.10

Step by Step Solution

1. Step 1: Write the proportion equation
   2,311.90 : 3,468.72 = 1,388.10 : x
2. Step 2: Convert to fraction form
   2,311.90/3,468.72 = 1,388.10/x
3. Step 3: Cross multiply
   2,311.90x = 3,468.72 × 1,388.10
4. Step 4: Simplify right side
   2,311.90x = 4,814,941.13
5. Step 5: Solve for x
   x = 4,814,941.13/2,311.90
6. Step 6: Final answer
   x = 2,082.68