Finding the Fourth Proportional to 2,585.40, 3,876.54 and 918.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,585.40 : 3,876.54 = 918.72 : x
2. Step 2: Convert to fraction form
   2,585.40/3,876.54 = 918.72/x
3. Step 3: Cross multiply
   2,585.40x = 3,876.54 × 918.72
4. Step 4: Simplify right side
   2,585.40x = 3,561,454.83
5. Step 5: Solve for x
   x = 3,561,454.83/2,585.40
6. Step 6: Final answer
   x = 1,377.53