Finding the Fourth Proportional to 1,019.85, 1,407.27 and 577.71

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.85 : 1,407.27 = 577.71 : x
2. Step 2: Convert to fraction form
   1,019.85/1,407.27 = 577.71/x
3. Step 3: Cross multiply
   1,019.85x = 1,407.27 × 577.71
4. Step 4: Simplify right side
   1,019.85x = 812,993.95
5. Step 5: Solve for x
   x = 812,993.95/1,019.85
6. Step 6: Final answer
   x = 797.17