Finding the Fourth Proportional to 1,168.51, 1,612.62 and 644.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,168.51 : 1,612.62 = 644.55 : x
2. Step 2: Convert to fraction form
   1,168.51/1,612.62 = 644.55/x
3. Step 3: Cross multiply
   1,168.51x = 1,612.62 × 644.55
4. Step 4: Simplify right side
   1,168.51x = 1,039,414.22
5. Step 5: Solve for x
   x = 1,039,414.22/1,168.51
6. Step 6: Final answer
   x = 889.52