Finding the Fourth Proportional to 2,105.46, 3,156.35 and 872.10

Step by Step Solution

1. Step 1: Write the proportion equation
   2,105.46 : 3,156.35 = 872.10 : x
2. Step 2: Convert to fraction form
   2,105.46/3,156.35 = 872.10/x
3. Step 3: Cross multiply
   2,105.46x = 3,156.35 × 872.10
4. Step 4: Simplify right side
   2,105.46x = 2,752,648.47
5. Step 5: Solve for x
   x = 2,752,648.47/2,105.46
6. Step 6: Final answer
   x = 1,307.39