Finding the Fourth Proportional to 2,127.79, 2,936.60 and 1,288.47

Step by Step Solution

1. Step 1: Write the proportion equation
   2,127.79 : 2,936.60 = 1,288.47 : x
2. Step 2: Convert to fraction form
   2,127.79/2,936.60 = 1,288.47/x
3. Step 3: Cross multiply
   2,127.79x = 2,936.60 × 1,288.47
4. Step 4: Simplify right side
   2,127.79x = 3,783,709.25
5. Step 5: Solve for x
   x = 3,783,709.25/2,127.79
6. Step 6: Final answer
   x = 1,778.24