Finding the Fourth Proportional to 1,581.54, 2,181.62 and 918.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,581.54 : 2,181.62 = 918.31 : x
2. Step 2: Convert to fraction form
   1,581.54/2,181.62 = 918.31/x
3. Step 3: Cross multiply
   1,581.54x = 2,181.62 × 918.31
4. Step 4: Simplify right side
   1,581.54x = 2,003,387.96
5. Step 5: Solve for x
   x = 2,003,387.96/1,581.54
6. Step 6: Final answer
   x = 1,266.73