Finding the Fourth Proportional to 498.56, 687.29 and 443.21

Step by Step Solution

1. Step 1: Write the proportion equation
   498.56 : 687.29 = 443.21 : x
2. Step 2: Convert to fraction form
   498.56/687.29 = 443.21/x
3. Step 3: Cross multiply
   498.56x = 687.29 × 443.21
4. Step 4: Simplify right side
   498.56x = 304,608.15
5. Step 5: Solve for x
   x = 304,608.15/498.56
6. Step 6: Final answer
   x = 610.98