Finding the Fourth Proportional to 2,105.45, 3,158.67 and 644.59

Step by Step Solution

1. Step 1: Write the proportion equation
   2,105.45 : 3,158.67 = 644.59 : x
2. Step 2: Convert to fraction form
   2,105.45/3,158.67 = 644.59/x
3. Step 3: Cross multiply
   2,105.45x = 3,158.67 × 644.59
4. Step 4: Simplify right side
   2,105.45x = 2,036,053.46
5. Step 5: Solve for x
   x = 2,036,053.46/2,105.45
6. Step 6: Final answer
   x = 967.04