Finding the Fourth Proportional to 2,128.26, 3,189.62 and 1,087.39

Step by Step Solution

1. Step 1: Write the proportion equation
   2,128.26 : 3,189.62 = 1,087.39 : x
2. Step 2: Convert to fraction form
   2,128.26/3,189.62 = 1,087.39/x
3. Step 3: Cross multiply
   2,128.26x = 3,189.62 × 1,087.39
4. Step 4: Simplify right side
   2,128.26x = 3,468,349.59
5. Step 5: Solve for x
   x = 3,468,349.59/2,128.26
6. Step 6: Final answer
   x = 1,629.66