Finding the Fourth Proportional to 1,111.38, 1,663.98 and 721.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.38 : 1,663.98 = 721.83 : x
2. Step 2: Convert to fraction form
   1,111.38/1,663.98 = 721.83/x
3. Step 3: Cross multiply
   1,111.38x = 1,663.98 × 721.83
4. Step 4: Simplify right side
   1,111.38x = 1,201,110.68
5. Step 5: Solve for x
   x = 1,201,110.68/1,111.38
6. Step 6: Final answer
   x = 1,080.74