Finding the Fourth Proportional to 1,018.42, 1,528.58 and 402.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,018.42 : 1,528.58 = 402.55 : x
2. Step 2: Convert to fraction form
   1,018.42/1,528.58 = 402.55/x
3. Step 3: Cross multiply
   1,018.42x = 1,528.58 × 402.55
4. Step 4: Simplify right side
   1,018.42x = 615,329.88
5. Step 5: Solve for x
   x = 615,329.88/1,018.42
6. Step 6: Final answer
   x = 604.20