Finding the Fourth Proportional to 2,879.75, 4,318.72 and 931.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,879.75 : 4,318.72 = 931.50 : x
2. Step 2: Convert to fraction form
   2,879.75/4,318.72 = 931.50/x
3. Step 3: Cross multiply
   2,879.75x = 4,318.72 × 931.50
4. Step 4: Simplify right side
   2,879.75x = 4,022,885.35
5. Step 5: Solve for x
   x = 4,022,885.35/2,879.75
6. Step 6: Final answer
   x = 1,396.96