Finding the Fourth Proportional to 1,721.86, 2,565.69 and 1,638.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,721.86 : 2,565.69 = 1,638.18 : x
2. Step 2: Convert to fraction form
   1,721.86/2,565.69 = 1,638.18/x
3. Step 3: Cross multiply
   1,721.86x = 2,565.69 × 1,638.18
4. Step 4: Simplify right side
   1,721.86x = 4,203,055.90
5. Step 5: Solve for x
   x = 4,203,055.90/1,721.86
6. Step 6: Final answer
   x = 2,441.00