Finding the Fourth Proportional to 1,013.31, 1,520.24 and 320.00

Step by Step Solution

1. Step 1: Write the proportion equation
   1,013.31 : 1,520.24 = 320.00 : x
2. Step 2: Convert to fraction form
   1,013.31/1,520.24 = 320.00/x
3. Step 3: Cross multiply
   1,013.31x = 1,520.24 × 320.00
4. Step 4: Simplify right side
   1,013.31x = 486,467.60
5. Step 5: Solve for x
   x = 486,467.60/1,013.31
6. Step 6: Final answer
   x = 480.08