Finding the Fourth Proportional to 1,168.48, 1,612.50 and 644.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,168.48 : 1,612.50 = 644.50 : x
2. Step 2: Convert to fraction form
   1,168.48/1,612.50 = 644.50/x
3. Step 3: Cross multiply
   1,168.48x = 1,612.50 × 644.50
4. Step 4: Simplify right side
   1,168.48x = 1,039,256.25
5. Step 5: Solve for x
   x = 1,039,256.25/1,168.48
6. Step 6: Final answer
   x = 889.41