Finding the Fourth Proportional to 1,056.42, 1,584.61 and 398.27

Step by Step Solution

1. Step 1: Write the proportion equation
   1,056.42 : 1,584.61 = 398.27 : x
2. Step 2: Convert to fraction form
   1,056.42/1,584.61 = 398.27/x
3. Step 3: Cross multiply
   1,056.42x = 1,584.61 × 398.27
4. Step 4: Simplify right side
   1,056.42x = 631,105.59
5. Step 5: Solve for x
   x = 631,105.59/1,056.42
6. Step 6: Final answer
   x = 597.40