Finding the Fourth Proportional to 498.82, 688.42 and 415.78

Step by Step Solution

1. Step 1: Write the proportion equation
   498.82 : 688.42 = 415.78 : x
2. Step 2: Convert to fraction form
   498.82/688.42 = 415.78/x
3. Step 3: Cross multiply
   498.82x = 688.42 × 415.78
4. Step 4: Simplify right side
   498.82x = 286,231.27
5. Step 5: Solve for x
   x = 286,231.27/498.82
6. Step 6: Final answer
   x = 573.82