Finding the Fourth Proportional to 1,019.88, 1,528.29 and 609.21

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.88 : 1,528.29 = 609.21 : x
2. Step 2: Convert to fraction form
   1,019.88/1,528.29 = 609.21/x
3. Step 3: Cross multiply
   1,019.88x = 1,528.29 × 609.21
4. Step 4: Simplify right side
   1,019.88x = 931,049.55
5. Step 5: Solve for x
   x = 931,049.55/1,019.88
6. Step 6: Final answer
   x = 912.90