Finding the Fourth Proportional to 1,439.98, 2,158.38 and 618.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,439.98 : 2,158.38 = 618.82 : x
2. Step 2: Convert to fraction form
   1,439.98/2,158.38 = 618.82/x
3. Step 3: Cross multiply
   1,439.98x = 2,158.38 × 618.82
4. Step 4: Simplify right side
   1,439.98x = 1,335,648.71
5. Step 5: Solve for x
   x = 1,335,648.71/1,439.98
6. Step 6: Final answer
   x = 927.55