Finding the Fourth Proportional to 1,141.43, 1,575.18 and 644.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,141.43 : 1,575.18 = 644.09 : x
2. Step 2: Convert to fraction form
   1,141.43/1,575.18 = 644.09/x
3. Step 3: Cross multiply
   1,141.43x = 1,575.18 × 644.09
4. Step 4: Simplify right side
   1,141.43x = 1,014,549.81
5. Step 5: Solve for x
   x = 1,014,549.81/1,141.43
6. Step 6: Final answer
   x = 888.84