Finding the Fourth Proportional to 2,604.96, 3,906.72 and 872.64

Step by Step Solution

1. Step 1: Write the proportion equation
   2,604.96 : 3,906.72 = 872.64 : x
2. Step 2: Convert to fraction form
   2,604.96/3,906.72 = 872.64/x
3. Step 3: Cross multiply
   2,604.96x = 3,906.72 × 872.64
4. Step 4: Simplify right side
   2,604.96x = 3,409,160.14
5. Step 5: Solve for x
   x = 3,409,160.14/2,604.96
6. Step 6: Final answer
   x = 1,308.72