Finding the Fourth Proportional to 1,601.54, 2,401.72 and 821.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,601.54 : 2,401.72 = 821.28 : x
2. Step 2: Convert to fraction form
   1,601.54/2,401.72 = 821.28/x
3. Step 3: Cross multiply
   1,601.54x = 2,401.72 × 821.28
4. Step 4: Simplify right side
   1,601.54x = 1,972,482.55
5. Step 5: Solve for x
   x = 1,972,482.55/1,601.54
6. Step 6: Final answer
   x = 1,231.62