Finding the Fourth Proportional to 2,603.43, 3,905.18 and 872.05

Step by Step Solution

1. Step 1: Write the proportion equation
   2,603.43 : 3,905.18 = 872.05 : x
2. Step 2: Convert to fraction form
   2,603.43/3,905.18 = 872.05/x
3. Step 3: Cross multiply
   2,603.43x = 3,905.18 × 872.05
4. Step 4: Simplify right side
   2,603.43x = 3,405,512.22
5. Step 5: Solve for x
   x = 3,405,512.22/2,603.43
6. Step 6: Final answer
   x = 1,308.09