Finding the Fourth Proportional to 2,128.61, 2,937.53 and 1,289.18

Step by Step Solution

1. Step 1: Write the proportion equation
   2,128.61 : 2,937.53 = 1,289.18 : x
2. Step 2: Convert to fraction form
   2,128.61/2,937.53 = 1,289.18/x
3. Step 3: Cross multiply
   2,128.61x = 2,937.53 × 1,289.18
4. Step 4: Simplify right side
   2,128.61x = 3,787,015.49
5. Step 5: Solve for x
   x = 3,787,015.49/2,128.61
6. Step 6: Final answer
   x = 1,779.10