Finding the Fourth Proportional to 1,057.67, 1,459.41 and 664.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,057.67 : 1,459.41 = 664.42 : x
2. Step 2: Convert to fraction form
   1,057.67/1,459.41 = 664.42/x
3. Step 3: Cross multiply
   1,057.67x = 1,459.41 × 664.42
4. Step 4: Simplify right side
   1,057.67x = 969,659.20
5. Step 5: Solve for x
   x = 969,659.20/1,057.67
6. Step 6: Final answer
   x = 916.79