Finding the Fourth Proportional to 1,020.42, 1,531.17 and 443.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,020.42 : 1,531.17 = 443.25 : x
2. Step 2: Convert to fraction form
   1,020.42/1,531.17 = 443.25/x
3. Step 3: Cross multiply
   1,020.42x = 1,531.17 × 443.25
4. Step 4: Simplify right side
   1,020.42x = 678,691.10
5. Step 5: Solve for x
   x = 678,691.10/1,020.42
6. Step 6: Final answer
   x = 665.11