Finding the Fourth Proportional to 2,105.01, 3,158.06 and 644.18

Step by Step Solution

1. Step 1: Write the proportion equation
   2,105.01 : 3,158.06 = 644.18 : x
2. Step 2: Convert to fraction form
   2,105.01/3,158.06 = 644.18/x
3. Step 3: Cross multiply
   2,105.01x = 3,158.06 × 644.18
4. Step 4: Simplify right side
   2,105.01x = 2,034,340.08
5. Step 5: Solve for x
   x = 2,034,340.08/2,105.01
6. Step 6: Final answer
   x = 966.43