Finding the Fourth Proportional to 1,168.94, 1,613.13 and 644.98

Step by Step Solution

1. Step 1: Write the proportion equation
   1,168.94 : 1,613.13 = 644.98 : x
2. Step 2: Convert to fraction form
   1,168.94/1,613.13 = 644.98/x
3. Step 3: Cross multiply
   1,168.94x = 1,613.13 × 644.98
4. Step 4: Simplify right side
   1,168.94x = 1,040,436.59
5. Step 5: Solve for x
   x = 1,040,436.59/1,168.94
6. Step 6: Final answer
   x = 890.07