Finding the Fourth Proportional to 1,019.39, 1,406.74 and 577.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.39 : 1,406.74 = 577.31 : x
2. Step 2: Convert to fraction form
   1,019.39/1,406.74 = 577.31/x
3. Step 3: Cross multiply
   1,019.39x = 1,406.74 × 577.31
4. Step 4: Simplify right side
   1,019.39x = 812,125.07
5. Step 5: Solve for x
   x = 812,125.07/1,019.39
6. Step 6: Final answer
   x = 796.68