Finding the Fourth Proportional to 2,105.04, 3,155.28 and 872.40

Step by Step Solution

1. Step 1: Write the proportion equation
   2,105.04 : 3,155.28 = 872.40 : x
2. Step 2: Convert to fraction form
   2,105.04/3,155.28 = 872.40/x
3. Step 3: Cross multiply
   2,105.04x = 3,155.28 × 872.40
4. Step 4: Simplify right side
   2,105.04x = 2,752,666.27
5. Step 5: Solve for x
   x = 2,752,666.27/2,105.04
6. Step 6: Final answer
   x = 1,307.66