Finding the Fourth Proportional to 1,008.72, 1,512.72 and 359.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,008.72 : 1,512.72 = 359.28 : x
2. Step 2: Convert to fraction form
   1,008.72/1,512.72 = 359.28/x
3. Step 3: Cross multiply
   1,008.72x = 1,512.72 × 359.28
4. Step 4: Simplify right side
   1,008.72x = 543,490.04
5. Step 5: Solve for x
   x = 543,490.04/1,008.72
6. Step 6: Final answer
   x = 538.79