Finding the Fourth Proportional to 2,379.91, 3,569.17 and 918.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,379.91 : 3,569.17 = 918.72 : x
2. Step 2: Convert to fraction form
   2,379.91/3,569.17 = 918.72/x
3. Step 3: Cross multiply
   2,379.91x = 3,569.17 × 918.72
4. Step 4: Simplify right side
   2,379.91x = 3,279,067.86
5. Step 5: Solve for x
   x = 3,279,067.86/2,379.91
6. Step 6: Final answer
   x = 1,377.81