Finding the Fourth Proportional to 1,061.55, 1,591.91 and 445.54

Step by Step Solution

1. Step 1: Write the proportion equation
   1,061.55 : 1,591.91 = 445.54 : x
2. Step 2: Convert to fraction form
   1,061.55/1,591.91 = 445.54/x
3. Step 3: Cross multiply
   1,061.55x = 1,591.91 × 445.54
4. Step 4: Simplify right side
   1,061.55x = 709,259.58
5. Step 5: Solve for x
   x = 709,259.58/1,061.55
6. Step 6: Final answer
   x = 668.14