Finding the Fourth Proportional to 498.21, 687.24 and 323.25

Step by Step Solution

1. Step 1: Write the proportion equation
   498.21 : 687.24 = 323.25 : x
2. Step 2: Convert to fraction form
   498.21/687.24 = 323.25/x
3. Step 3: Cross multiply
   498.21x = 687.24 × 323.25
4. Step 4: Simplify right side
   498.21x = 222,150.33
5. Step 5: Solve for x
   x = 222,150.33/498.21
6. Step 6: Final answer
   x = 445.90