Finding the Fourth Proportional to 1,578.31, 2,178.61 and 1,082.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,578.31 : 2,178.61 = 1,082.59 : x
2. Step 2: Convert to fraction form
   1,578.31/2,178.61 = 1,082.59/x
3. Step 3: Cross multiply
   1,578.31x = 2,178.61 × 1,082.59
4. Step 4: Simplify right side
   1,578.31x = 2,358,541.40
5. Step 5: Solve for x
   x = 2,358,541.40/1,578.31
6. Step 6: Final answer
   x = 1,494.35