Finding the Fourth Proportional to 1,018.79, 1,529.20 and 688.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,018.79 : 1,529.20 = 688.69 : x
2. Step 2: Convert to fraction form
   1,018.79/1,529.20 = 688.69/x
3. Step 3: Cross multiply
   1,018.79x = 1,529.20 × 688.69
4. Step 4: Simplify right side
   1,018.79x = 1,053,140.86
5. Step 5: Solve for x
   x = 1,053,140.86/1,018.79
6. Step 6: Final answer
   x = 1,033.72