Finding the Fourth Proportional to 1,158.37, 1,736.78 and 638.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,158.37 : 1,736.78 = 638.62 : x
2. Step 2: Convert to fraction form
   1,158.37/1,736.78 = 638.62/x
3. Step 3: Cross multiply
   1,158.37x = 1,736.78 × 638.62
4. Step 4: Simplify right side
   1,158.37x = 1,109,142.44
5. Step 5: Solve for x
   x = 1,109,142.44/1,158.37
6. Step 6: Final answer
   x = 957.50