Finding the Fourth Proportional to 1,574.71, 2,173.57 and 911.86

Step by Step Solution

1. Step 1: Write the proportion equation
   1,574.71 : 2,173.57 = 911.86 : x
2. Step 2: Convert to fraction form
   1,574.71/2,173.57 = 911.86/x
3. Step 3: Cross multiply
   1,574.71x = 2,173.57 × 911.86
4. Step 4: Simplify right side
   1,574.71x = 1,981,983.83
5. Step 5: Solve for x
   x = 1,981,983.83/1,574.71
6. Step 6: Final answer
   x = 1,258.64