Finding the Fourth Proportional to 1,721.28, 2,579.31 and 1,356.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,721.28 : 2,579.31 = 1,356.78 : x
2. Step 2: Convert to fraction form
   1,721.28/2,579.31 = 1,356.78/x
3. Step 3: Cross multiply
   1,721.28x = 2,579.31 × 1,356.78
4. Step 4: Simplify right side
   1,721.28x = 3,499,556.22
5. Step 5: Solve for x
   x = 3,499,556.22/1,721.28
6. Step 6: Final answer
   x = 2,033.11