Finding the Fourth Proportional to 1,039.56, 1,434.64 and 573.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,039.56 : 1,434.64 = 573.80 : x
2. Step 2: Convert to fraction form
   1,039.56/1,434.64 = 573.80/x
3. Step 3: Cross multiply
   1,039.56x = 1,434.64 × 573.80
4. Step 4: Simplify right side
   1,039.56x = 823,196.43
5. Step 5: Solve for x
   x = 823,196.43/1,039.56
6. Step 6: Final answer
   x = 791.87