Finding the Fourth Proportional to 1,573.72, 2,171.81 and 910.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,573.72 : 2,171.81 = 910.80 : x
2. Step 2: Convert to fraction form
   1,573.72/2,171.81 = 910.80/x
3. Step 3: Cross multiply
   1,573.72x = 2,171.81 × 910.80
4. Step 4: Simplify right side
   1,573.72x = 1,978,086.83
5. Step 5: Solve for x
   x = 1,978,086.83/1,573.72
6. Step 6: Final answer
   x = 1,256.95