Finding the Fourth Proportional to 1,168.89, 1,613.04 and 644.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,168.89 : 1,613.04 = 644.91 : x
2. Step 2: Convert to fraction form
   1,168.89/1,613.04 = 644.91/x
3. Step 3: Cross multiply
   1,168.89x = 1,613.04 × 644.91
4. Step 4: Simplify right side
   1,168.89x = 1,040,265.63
5. Step 5: Solve for x
   x = 1,040,265.63/1,168.89
6. Step 6: Final answer
   x = 889.96