Finding the Fourth Proportional to 2,103.22, 3,155.19 and 642.10

Step by Step Solution

1. Step 1: Write the proportion equation
   2,103.22 : 3,155.19 = 642.10 : x
2. Step 2: Convert to fraction form
   2,103.22/3,155.19 = 642.10/x
3. Step 3: Cross multiply
   2,103.22x = 3,155.19 × 642.10
4. Step 4: Simplify right side
   2,103.22x = 2,025,947.50
5. Step 5: Solve for x
   x = 2,025,947.50/2,103.22
6. Step 6: Final answer
   x = 963.26