Finding the Fourth Proportional to 2,105.69, 3,159.03 and 644.81

Step by Step Solution

1. Step 1: Write the proportion equation
   2,105.69 : 3,159.03 = 644.81 : x
2. Step 2: Convert to fraction form
   2,105.69/3,159.03 = 644.81/x
3. Step 3: Cross multiply
   2,105.69x = 3,159.03 × 644.81
4. Step 4: Simplify right side
   2,105.69x = 2,036,974.13
5. Step 5: Solve for x
   x = 2,036,974.13/2,105.69
6. Step 6: Final answer
   x = 967.37