Finding the Fourth Proportional to 1,110.38, 1,665.59 and 288.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,110.38 : 1,665.59 = 288.72 : x
2. Step 2: Convert to fraction form
   1,110.38/1,665.59 = 288.72/x
3. Step 3: Cross multiply
   1,110.38x = 1,665.59 × 288.72
4. Step 4: Simplify right side
   1,110.38x = 480,887.70
5. Step 5: Solve for x
   x = 480,887.70/1,110.38
6. Step 6: Final answer
   x = 433.09