Finding the Fourth Proportional to 456.15, 680.50 and 443.59

Step by Step Solution

1. Step 1: Write the proportion equation
   456.15 : 680.50 = 443.59 : x
2. Step 2: Convert to fraction form
   456.15/680.50 = 443.59/x
3. Step 3: Cross multiply
   456.15x = 680.50 × 443.59
4. Step 4: Simplify right side
   456.15x = 301,861.89
5. Step 5: Solve for x
   x = 301,861.89/456.15
6. Step 6: Final answer
   x = 661.77