Finding the Fourth Proportional to 1,137.33, 1,569.53 and 639.94

Step by Step Solution

1. Step 1: Write the proportion equation
   1,137.33 : 1,569.53 = 639.94 : x
2. Step 2: Convert to fraction form
   1,137.33/1,569.53 = 639.94/x
3. Step 3: Cross multiply
   1,137.33x = 1,569.53 × 639.94
4. Step 4: Simplify right side
   1,137.33x = 1,004,405.03
5. Step 5: Solve for x
   x = 1,004,405.03/1,137.33
6. Step 6: Final answer
   x = 883.13