Finding the Fourth Proportional to 1,605.31, 2,211.89 and 1,080.43

Step by Step Solution

1. Step 1: Write the proportion equation
   1,605.31 : 2,211.89 = 1,080.43 : x
2. Step 2: Convert to fraction form
   1,605.31/2,211.89 = 1,080.43/x
3. Step 3: Cross multiply
   1,605.31x = 2,211.89 × 1,080.43
4. Step 4: Simplify right side
   1,605.31x = 2,389,792.31
5. Step 5: Solve for x
   x = 2,389,792.31/1,605.31
6. Step 6: Final answer
   x = 1,488.68