Finding the Fourth Proportional to 1,111.71, 1,667.54 and 289.97

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.71 : 1,667.54 = 289.97 : x
2. Step 2: Convert to fraction form
   1,111.71/1,667.54 = 289.97/x
3. Step 3: Cross multiply
   1,111.71x = 1,667.54 × 289.97
4. Step 4: Simplify right side
   1,111.71x = 483,528.96
5. Step 5: Solve for x
   x = 483,528.96/1,111.71
6. Step 6: Final answer
   x = 434.94