Finding the Fourth Proportional to 1,016.02, 1,524.12 and 399.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,016.02 : 1,524.12 = 399.78 : x
2. Step 2: Convert to fraction form
   1,016.02/1,524.12 = 399.78/x
3. Step 3: Cross multiply
   1,016.02x = 1,524.12 × 399.78
4. Step 4: Simplify right side
   1,016.02x = 609,312.69
5. Step 5: Solve for x
   x = 609,312.69/1,016.02
6. Step 6: Final answer
   x = 599.71