Finding the Fourth Proportional to 1,064.57, 1,469.12 and 644.92

Step by Step Solution

1. Step 1: Write the proportion equation
   1,064.57 : 1,469.12 = 644.92 : x
2. Step 2: Convert to fraction form
   1,064.57/1,469.12 = 644.92/x
3. Step 3: Cross multiply
   1,064.57x = 1,469.12 × 644.92
4. Step 4: Simplify right side
   1,064.57x = 947,464.87
5. Step 5: Solve for x
   x = 947,464.87/1,064.57
6. Step 6: Final answer
   x = 890.00