Finding the Fourth Proportional to 1,168.57, 1,612.73 and 644.70

Step by Step Solution

1. Step 1: Write the proportion equation
   1,168.57 : 1,612.73 = 644.70 : x
2. Step 2: Convert to fraction form
   1,168.57/1,612.73 = 644.70/x
3. Step 3: Cross multiply
   1,168.57x = 1,612.73 × 644.70
4. Step 4: Simplify right side
   1,168.57x = 1,039,727.03
5. Step 5: Solve for x
   x = 1,039,727.03/1,168.57
6. Step 6: Final answer
   x = 889.74