Finding the Fourth Proportional to 1,064.69, 1,468.92 and 644.90

Step by Step Solution

1. Step 1: Write the proportion equation
   1,064.69 : 1,468.92 = 644.90 : x
2. Step 2: Convert to fraction form
   1,064.69/1,468.92 = 644.90/x
3. Step 3: Cross multiply
   1,064.69x = 1,468.92 × 644.90
4. Step 4: Simplify right side
   1,064.69x = 947,306.51
5. Step 5: Solve for x
   x = 947,306.51/1,064.69
6. Step 6: Final answer
   x = 889.75