Finding the Fourth Proportional to 1,116.28, 1,662.62 and 1,057.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,116.28 : 1,662.62 = 1,057.72 : x
2. Step 2: Convert to fraction form
   1,116.28/1,662.62 = 1,057.72/x
3. Step 3: Cross multiply
   1,116.28x = 1,662.62 × 1,057.72
4. Step 4: Simplify right side
   1,116.28x = 1,758,586.43
5. Step 5: Solve for x
   x = 1,758,586.43/1,116.28
6. Step 6: Final answer
   x = 1,575.40