Finding the Fourth Proportional to 498.72, 688.32 and 291.84

Step by Step Solution

1. Step 1: Write the proportion equation
   498.72 : 688.32 = 291.84 : x
2. Step 2: Convert to fraction form
   498.72/688.32 = 291.84/x
3. Step 3: Cross multiply
   498.72x = 688.32 × 291.84
4. Step 4: Simplify right side
   498.72x = 200,879.31
5. Step 5: Solve for x
   x = 200,879.31/498.72
6. Step 6: Final answer
   x = 402.79