Finding the Fourth Proportional to 1,111.06, 1,666.68 and 320.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.06 : 1,666.68 = 320.42 : x
2. Step 2: Convert to fraction form
   1,111.06/1,666.68 = 320.42/x
3. Step 3: Cross multiply
   1,111.06x = 1,666.68 × 320.42
4. Step 4: Simplify right side
   1,111.06x = 534,043.27
5. Step 5: Solve for x
   x = 534,043.27/1,111.06
6. Step 6: Final answer
   x = 480.66