Finding the Fourth Proportional to 1,061.32, 1,591.86 and 320.85

Step by Step Solution

1. Step 1: Write the proportion equation
   1,061.32 : 1,591.86 = 320.85 : x
2. Step 2: Convert to fraction form
   1,061.32/1,591.86 = 320.85/x
3. Step 3: Cross multiply
   1,061.32x = 1,591.86 × 320.85
4. Step 4: Simplify right side
   1,061.32x = 510,748.28
5. Step 5: Solve for x
   x = 510,748.28/1,061.32
6. Step 6: Final answer
   x = 481.24