Finding the Fourth Proportional to 1,581.15, 2,181.74 and 917.94

Step by Step Solution

1. Step 1: Write the proportion equation
   1,581.15 : 2,181.74 = 917.94 : x
2. Step 2: Convert to fraction form
   1,581.15/2,181.74 = 917.94/x
3. Step 3: Cross multiply
   1,581.15x = 2,181.74 × 917.94
4. Step 4: Simplify right side
   1,581.15x = 2,002,701.83
5. Step 5: Solve for x
   x = 2,002,701.83/1,581.15
6. Step 6: Final answer
   x = 1,266.61