Finding the Fourth Proportional to 2,142.31, 3,211.14 and 1,399.58

Step by Step Solution

1. Step 1: Write the proportion equation
   2,142.31 : 3,211.14 = 1,399.58 : x
2. Step 2: Convert to fraction form
   2,142.31/3,211.14 = 1,399.58/x
3. Step 3: Cross multiply
   2,142.31x = 3,211.14 × 1,399.58
4. Step 4: Simplify right side
   2,142.31x = 4,494,248.56
5. Step 5: Solve for x
   x = 4,494,248.56/2,142.31
6. Step 6: Final answer
   x = 2,097.85