Finding the Fourth Proportional to 1,019.10, 1,528.52 and 288.74

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.10 : 1,528.52 = 288.74 : x
2. Step 2: Convert to fraction form
   1,019.10/1,528.52 = 288.74/x
3. Step 3: Cross multiply
   1,019.10x = 1,528.52 × 288.74
4. Step 4: Simplify right side
   1,019.10x = 441,344.86
5. Step 5: Solve for x
   x = 441,344.86/1,019.10
6. Step 6: Final answer
   x = 433.07