Finding the Fourth Proportional to 1,721.69, 2,588.31 and 1,378.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,721.69 : 2,588.31 = 1,378.78 : x
2. Step 2: Convert to fraction form
   1,721.69/2,588.31 = 1,378.78/x
3. Step 3: Cross multiply
   1,721.69x = 2,588.31 × 1,378.78
4. Step 4: Simplify right side
   1,721.69x = 3,568,710.06
5. Step 5: Solve for x
   x = 3,568,710.06/1,721.69
6. Step 6: Final answer
   x = 2,072.79