Finding the Fourth Proportional to 789.12, 1,088.72 and 457.42

Step by Step Solution

1. Step 1: Write the proportion equation
   789.12 : 1,088.72 = 457.42 : x
2. Step 2: Convert to fraction form
   789.12/1,088.72 = 457.42/x
3. Step 3: Cross multiply
   789.12x = 1,088.72 × 457.42
4. Step 4: Simplify right side
   789.12x = 498,002.83
5. Step 5: Solve for x
   x = 498,002.83/789.12
6. Step 6: Final answer
   x = 631.09