Finding the Fourth Proportional to 498.06, 687.27 and 288.25

Step by Step Solution

1. Step 1: Write the proportion equation
   498.06 : 687.27 = 288.25 : x
2. Step 2: Convert to fraction form
   498.06/687.27 = 288.25/x
3. Step 3: Cross multiply
   498.06x = 687.27 × 288.25
4. Step 4: Simplify right side
   498.06x = 198,105.58
5. Step 5: Solve for x
   x = 198,105.58/498.06
6. Step 6: Final answer
   x = 397.75