Finding the Fourth Proportional to 1,309.25, 1,806.72 and 711.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,309.25 : 1,806.72 = 711.72 : x
2. Step 2: Convert to fraction form
   1,309.25/1,806.72 = 711.72/x
3. Step 3: Cross multiply
   1,309.25x = 1,806.72 × 711.72
4. Step 4: Simplify right side
   1,309.25x = 1,285,878.76
5. Step 5: Solve for x
   x = 1,285,878.76/1,309.25
6. Step 6: Final answer
   x = 982.15