Finding the Fourth Proportional to 1,581.21, 2,182.05 and 918.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,581.21 : 2,182.05 = 918.15 : x
2. Step 2: Convert to fraction form
   1,581.21/2,182.05 = 918.15/x
3. Step 3: Cross multiply
   1,581.21x = 2,182.05 × 918.15
4. Step 4: Simplify right side
   1,581.21x = 2,003,449.21
5. Step 5: Solve for x
   x = 2,003,449.21/1,581.21
6. Step 6: Final answer
   x = 1,267.04