Finding the Fourth Proportional to 1,225.23, 1,690.72 and 728.04

Step by Step Solution

1. Step 1: Write the proportion equation
   1,225.23 : 1,690.72 = 728.04 : x
2. Step 2: Convert to fraction form
   1,225.23/1,690.72 = 728.04/x
3. Step 3: Cross multiply
   1,225.23x = 1,690.72 × 728.04
4. Step 4: Simplify right side
   1,225.23x = 1,230,910.89
5. Step 5: Solve for x
   x = 1,230,910.89/1,225.23
6. Step 6: Final answer
   x = 1,004.64