Finding the Fourth Proportional to 1,574.25, 2,172.27 and 911.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,574.25 : 2,172.27 = 911.31 : x
2. Step 2: Convert to fraction form
   1,574.25/2,172.27 = 911.31/x
3. Step 3: Cross multiply
   1,574.25x = 2,172.27 × 911.31
4. Step 4: Simplify right side
   1,574.25x = 1,979,611.37
5. Step 5: Solve for x
   x = 1,979,611.37/1,574.25
6. Step 6: Final answer
   x = 1,257.49