Finding the Fourth Proportional to 1,111.96, 1,668.01 and 290.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.96 : 1,668.01 = 290.25 : x
2. Step 2: Convert to fraction form
   1,111.96/1,668.01 = 290.25/x
3. Step 3: Cross multiply
   1,111.96x = 1,668.01 × 290.25
4. Step 4: Simplify right side
   1,111.96x = 484,139.90
5. Step 5: Solve for x
   x = 484,139.90/1,111.96
6. Step 6: Final answer
   x = 435.39