Finding the Fourth Proportional to 1,243.89, 1,716.59 and 720.23

Step by Step Solution

1. Step 1: Write the proportion equation
   1,243.89 : 1,716.59 = 720.23 : x
2. Step 2: Convert to fraction form
   1,243.89/1,716.59 = 720.23/x
3. Step 3: Cross multiply
   1,243.89x = 1,716.59 × 720.23
4. Step 4: Simplify right side
   1,243.89x = 1,236,332.83
5. Step 5: Solve for x
   x = 1,236,332.83/1,243.89
6. Step 6: Final answer
   x = 993.92