Finding the Fourth Proportional to 1,141.64, 1,575.59 and 644.37

Step by Step Solution

1. Step 1: Write the proportion equation
   1,141.64 : 1,575.59 = 644.37 : x
2. Step 2: Convert to fraction form
   1,141.64/1,575.59 = 644.37/x
3. Step 3: Cross multiply
   1,141.64x = 1,575.59 × 644.37
4. Step 4: Simplify right side
   1,141.64x = 1,015,262.93
5. Step 5: Solve for x
   x = 1,015,262.93/1,141.64
6. Step 6: Final answer
   x = 889.30