Finding the Fourth Proportional to 1,017.95, 1,404.63 and 644.27

Step by Step Solution

1. Step 1: Write the proportion equation
   1,017.95 : 1,404.63 = 644.27 : x
2. Step 2: Convert to fraction form
   1,017.95/1,404.63 = 644.27/x
3. Step 3: Cross multiply
   1,017.95x = 1,404.63 × 644.27
4. Step 4: Simplify right side
   1,017.95x = 904,953.95
5. Step 5: Solve for x
   x = 904,953.95/1,017.95
6. Step 6: Final answer
   x = 889.00