Finding the Fourth Proportional to 1,019.30, 1,528.49 and 434.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.30 : 1,528.49 = 434.57 : x
2. Step 2: Convert to fraction form
   1,019.30/1,528.49 = 434.57/x
3. Step 3: Cross multiply
   1,019.30x = 1,528.49 × 434.57
4. Step 4: Simplify right side
   1,019.30x = 664,229.34
5. Step 5: Solve for x
   x = 664,229.34/1,019.30
6. Step 6: Final answer
   x = 651.66