Finding the Fourth Proportional to 1,581.57, 2,181.78 and 918.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,581.57 : 2,181.78 = 918.18 : x
2. Step 2: Convert to fraction form
   1,581.57/2,181.78 = 918.18/x
3. Step 3: Cross multiply
   1,581.57x = 2,181.78 × 918.18
4. Step 4: Simplify right side
   1,581.57x = 2,003,266.76
5. Step 5: Solve for x
   x = 2,003,266.76/1,581.57
6. Step 6: Final answer
   x = 1,266.63