Finding the Fourth Proportional to 1,020.42, 1,530.72 and 290.03

Step by Step Solution

1. Step 1: Write the proportion equation
   1,020.42 : 1,530.72 = 290.03 : x
2. Step 2: Convert to fraction form
   1,020.42/1,530.72 = 290.03/x
3. Step 3: Cross multiply
   1,020.42x = 1,530.72 × 290.03
4. Step 4: Simplify right side
   1,020.42x = 443,947.07
5. Step 5: Solve for x
   x = 443,947.07/1,020.42
6. Step 6: Final answer
   x = 435.06