Finding the Fourth Proportional to 1,689.89, 2,331.38 and 1,100.21

Step by Step Solution

1. Step 1: Write the proportion equation
   1,689.89 : 2,331.38 = 1,100.21 : x
2. Step 2: Convert to fraction form
   1,689.89/2,331.38 = 1,100.21/x
3. Step 3: Cross multiply
   1,689.89x = 2,331.38 × 1,100.21
4. Step 4: Simplify right side
   1,689.89x = 2,565,002.09
5. Step 5: Solve for x
   x = 2,565,002.09/1,689.89
6. Step 6: Final answer
   x = 1,517.85