Finding the Fourth Proportional to 1,056.28, 1,457.72 and 584.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,056.28 : 1,457.72 = 584.20 : x
2. Step 2: Convert to fraction form
   1,056.28/1,457.72 = 584.20/x
3. Step 3: Cross multiply
   1,056.28x = 1,457.72 × 584.20
4. Step 4: Simplify right side
   1,056.28x = 851,600.02
5. Step 5: Solve for x
   x = 851,600.02/1,056.28
6. Step 6: Final answer
   x = 806.23