Finding the Fourth Proportional to 2,812.18, 4,218.72 and 1,057.32

Step by Step Solution

1. Step 1: Write the proportion equation
   2,812.18 : 4,218.72 = 1,057.32 : x
2. Step 2: Convert to fraction form
   2,812.18/4,218.72 = 1,057.32/x
3. Step 3: Cross multiply
   2,812.18x = 4,218.72 × 1,057.32
4. Step 4: Simplify right side
   2,812.18x = 4,460,537.03
5. Step 5: Solve for x
   x = 4,460,537.03/2,812.18
6. Step 6: Final answer
   x = 1,586.15