Finding the Fourth Proportional to 498.96, 688.50 and 277.89

Step by Step Solution

1. Step 1: Write the proportion equation
   498.96 : 688.50 = 277.89 : x
2. Step 2: Convert to fraction form
   498.96/688.50 = 277.89/x
3. Step 3: Cross multiply
   498.96x = 688.50 × 277.89
4. Step 4: Simplify right side
   498.96x = 191,327.27
5. Step 5: Solve for x
   x = 191,327.27/498.96
6. Step 6: Final answer
   x = 383.45