Finding the Fourth Proportional to 1,019.42, 1,528.07 and 402.87

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.42 : 1,528.07 = 402.87 : x
2. Step 2: Convert to fraction form
   1,019.42/1,528.07 = 402.87/x
3. Step 3: Cross multiply
   1,019.42x = 1,528.07 × 402.87
4. Step 4: Simplify right side
   1,019.42x = 615,613.56
5. Step 5: Solve for x
   x = 615,613.56/1,019.42
6. Step 6: Final answer
   x = 603.89