Finding the Fourth Proportional to 1,162.55, 1,604.32 and 638.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,162.55 : 1,604.32 = 638.57 : x
2. Step 2: Convert to fraction form
   1,162.55/1,604.32 = 638.57/x
3. Step 3: Cross multiply
   1,162.55x = 1,604.32 × 638.57
4. Step 4: Simplify right side
   1,162.55x = 1,024,473.04
5. Step 5: Solve for x
   x = 1,024,473.04/1,162.55
6. Step 6: Final answer
   x = 881.23