Finding the Fourth Proportional to 1,019.68, 1,405.92 and 724.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.68 : 1,405.92 = 724.72 : x
2. Step 2: Convert to fraction form
   1,019.68/1,405.92 = 724.72/x
3. Step 3: Cross multiply
   1,019.68x = 1,405.92 × 724.72
4. Step 4: Simplify right side
   1,019.68x = 1,018,898.34
5. Step 5: Solve for x
   x = 1,018,898.34/1,019.68
6. Step 6: Final answer
   x = 999.23