Finding the Fourth Proportional to 1,989.80, 2,745.88 and 1,105.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,989.80 : 2,745.88 = 1,105.59 : x
2. Step 2: Convert to fraction form
   1,989.80/2,745.88 = 1,105.59/x
3. Step 3: Cross multiply
   1,989.80x = 2,745.88 × 1,105.59
4. Step 4: Simplify right side
   1,989.80x = 3,035,817.47
5. Step 5: Solve for x
   x = 3,035,817.47/1,989.80
6. Step 6: Final answer
   x = 1,525.69