Finding the Fourth Proportional to 1,003.21, 1,384.79 and 723.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,003.21 : 1,384.79 = 723.61 : x
2. Step 2: Convert to fraction form
   1,003.21/1,384.79 = 723.61/x
3. Step 3: Cross multiply
   1,003.21x = 1,384.79 × 723.61
4. Step 4: Simplify right side
   1,003.21x = 1,002,047.89
5. Step 5: Solve for x
   x = 1,002,047.89/1,003.21
6. Step 6: Final answer
   x = 998.84