Finding the Fourth Proportional to 2,931.61, 4,398.21 and 1,057.69

Step by Step Solution

1. Step 1: Write the proportion equation
   2,931.61 : 4,398.21 = 1,057.69 : x
2. Step 2: Convert to fraction form
   2,931.61/4,398.21 = 1,057.69/x
3. Step 3: Cross multiply
   2,931.61x = 4,398.21 × 1,057.69
4. Step 4: Simplify right side
   2,931.61x = 4,651,942.73
5. Step 5: Solve for x
   x = 4,651,942.73/2,931.61
6. Step 6: Final answer
   x = 1,586.82