Finding the Fourth Proportional to 1,137.71, 1,707.89 and 644.22

Step by Step Solution

1. Step 1: Write the proportion equation
   1,137.71 : 1,707.89 = 644.22 : x
2. Step 2: Convert to fraction form
   1,137.71/1,707.89 = 644.22/x
3. Step 3: Cross multiply
   1,137.71x = 1,707.89 × 644.22
4. Step 4: Simplify right side
   1,137.71x = 1,100,253.67
5. Step 5: Solve for x
   x = 1,100,253.67/1,137.71
6. Step 6: Final answer
   x = 967.08