Finding the Fourth Proportional to 1,020.72, 1,406.80 and 722.04

Step by Step Solution

1. Step 1: Write the proportion equation
   1,020.72 : 1,406.80 = 722.04 : x
2. Step 2: Convert to fraction form
   1,020.72/1,406.80 = 722.04/x
3. Step 3: Cross multiply
   1,020.72x = 1,406.80 × 722.04
4. Step 4: Simplify right side
   1,020.72x = 1,015,765.87
5. Step 5: Solve for x
   x = 1,015,765.87/1,020.72
6. Step 6: Final answer
   x = 995.15