Finding the Fourth Proportional to 1,574.68, 2,172.72 and 911.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,574.68 : 2,172.72 = 911.56 : x
2. Step 2: Convert to fraction form
   1,574.68/2,172.72 = 911.56/x
3. Step 3: Cross multiply
   1,574.68x = 2,172.72 × 911.56
4. Step 4: Simplify right side
   1,574.68x = 1,980,564.64
5. Step 5: Solve for x
   x = 1,980,564.64/1,574.68
6. Step 6: Final answer
   x = 1,257.76