Finding the Fourth Proportional to 1,020.22, 1,407.56 and 578.03

Step by Step Solution

1. Step 1: Write the proportion equation
   1,020.22 : 1,407.56 = 578.03 : x
2. Step 2: Convert to fraction form
   1,020.22/1,407.56 = 578.03/x
3. Step 3: Cross multiply
   1,020.22x = 1,407.56 × 578.03
4. Step 4: Simplify right side
   1,020.22x = 813,601.98
5. Step 5: Solve for x
   x = 813,601.98/1,020.22
6. Step 6: Final answer
   x = 797.48