Finding the Fourth Proportional to 2,128.77, 2,937.23 and 1,289.47

Step by Step Solution

1. Step 1: Write the proportion equation
   2,128.77 : 2,937.23 = 1,289.47 : x
2. Step 2: Convert to fraction form
   2,128.77/2,937.23 = 1,289.47/x
3. Step 3: Cross multiply
   2,128.77x = 2,937.23 × 1,289.47
4. Step 4: Simplify right side
   2,128.77x = 3,787,469.97
5. Step 5: Solve for x
   x = 3,787,469.97/2,128.77
6. Step 6: Final answer
   x = 1,779.18