Finding the Fourth Proportional to 1,064.24, 1,468.74 and 644.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,064.24 : 1,468.74 = 644.80 : x
2. Step 2: Convert to fraction form
   1,064.24/1,468.74 = 644.80/x
3. Step 3: Cross multiply
   1,064.24x = 1,468.74 × 644.80
4. Step 4: Simplify right side
   1,064.24x = 947,043.55
5. Step 5: Solve for x
   x = 947,043.55/1,064.24
6. Step 6: Final answer
   x = 889.88