Finding the Fourth Proportional to 1,061.31, 1,591.97 and 445.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,061.31 : 1,591.97 = 445.31 : x
2. Step 2: Convert to fraction form
   1,061.31/1,591.97 = 445.31/x
3. Step 3: Cross multiply
   1,061.31x = 1,591.97 × 445.31
4. Step 4: Simplify right side
   1,061.31x = 708,909.97
5. Step 5: Solve for x
   x = 708,909.97/1,061.31
6. Step 6: Final answer
   x = 667.96