Finding the Fourth Proportional to 1,491.18, 2,057.72 and 818.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,491.18 : 2,057.72 = 818.88 : x
2. Step 2: Convert to fraction form
   1,491.18/2,057.72 = 818.88/x
3. Step 3: Cross multiply
   1,491.18x = 2,057.72 × 818.88
4. Step 4: Simplify right side
   1,491.18x = 1,685,025.75
5. Step 5: Solve for x
   x = 1,685,025.75/1,491.18
6. Step 6: Final answer
   x = 1,129.99