Finding the Fourth Proportional to 2,879.71, 4,320.20 and 931.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,879.71 : 4,320.20 = 931.89 : x
2. Step 2: Convert to fraction form
   2,879.71/4,320.20 = 931.89/x
3. Step 3: Cross multiply
   2,879.71x = 4,320.20 × 931.89
4. Step 4: Simplify right side
   2,879.71x = 4,025,951.18
5. Step 5: Solve for x
   x = 4,025,951.18/2,879.71
6. Step 6: Final answer
   x = 1,398.04