Finding the Fourth Proportional to 1,007.33, 1,510.83 and 390.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,007.33 : 1,510.83 = 390.96 : x
2. Step 2: Convert to fraction form
   1,007.33/1,510.83 = 390.96/x
3. Step 3: Cross multiply
   1,007.33x = 1,510.83 × 390.96
4. Step 4: Simplify right side
   1,007.33x = 590,674.10
5. Step 5: Solve for x
   x = 590,674.10/1,007.33
6. Step 6: Final answer
   x = 586.38