Finding the Fourth Proportional to 1,137.42, 1,569.42 and 640.04

Step by Step Solution

1. Step 1: Write the proportion equation
   1,137.42 : 1,569.42 = 640.04 : x
2. Step 2: Convert to fraction form
   1,137.42/1,569.42 = 640.04/x
3. Step 3: Cross multiply
   1,137.42x = 1,569.42 × 640.04
4. Step 4: Simplify right side
   1,137.42x = 1,004,483.73
5. Step 5: Solve for x
   x = 1,004,483.73/1,137.42
6. Step 6: Final answer
   x = 883.12