Finding the Fourth Proportional to 2,621.89, 3,928.72 and 1,234.90

Step by Step Solution

1. Step 1: Write the proportion equation
   2,621.89 : 3,928.72 = 1,234.90 : x
2. Step 2: Convert to fraction form
   2,621.89/3,928.72 = 1,234.90/x
3. Step 3: Cross multiply
   2,621.89x = 3,928.72 × 1,234.90
4. Step 4: Simplify right side
   2,621.89x = 4,851,576.33
5. Step 5: Solve for x
   x = 4,851,576.33/2,621.89
6. Step 6: Final answer
   x = 1,850.41