Finding the Fourth Proportional to 1,574.43, 2,172.54 and 911.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,574.43 : 2,172.54 = 911.15 : x
2. Step 2: Convert to fraction form
   1,574.43/2,172.54 = 911.15/x
3. Step 3: Cross multiply
   1,574.43x = 2,172.54 × 911.15
4. Step 4: Simplify right side
   1,574.43x = 1,979,505.27
5. Step 5: Solve for x
   x = 1,979,505.27/1,574.43
6. Step 6: Final answer
   x = 1,257.29