Finding the Fourth Proportional to 1,136.82, 1,568.86 and 639.46

Step by Step Solution

1. Step 1: Write the proportion equation
   1,136.82 : 1,568.86 = 639.46 : x
2. Step 2: Convert to fraction form
   1,136.82/1,568.86 = 639.46/x
3. Step 3: Cross multiply
   1,136.82x = 1,568.86 × 639.46
4. Step 4: Simplify right side
   1,136.82x = 1,003,223.22
5. Step 5: Solve for x
   x = 1,003,223.22/1,136.82
6. Step 6: Final answer
   x = 882.48