Finding the Fourth Proportional to 1,136.07, 1,567.72 and 638.73

Step by Step Solution

1. Step 1: Write the proportion equation
   1,136.07 : 1,567.72 = 638.73 : x
2. Step 2: Convert to fraction form
   1,136.07/1,567.72 = 638.73/x
3. Step 3: Cross multiply
   1,136.07x = 1,567.72 × 638.73
4. Step 4: Simplify right side
   1,136.07x = 1,001,338.76
5. Step 5: Solve for x
   x = 1,001,338.76/1,136.07
6. Step 6: Final answer
   x = 881.41