Finding the Fourth Proportional to 2,288.78, 3,158.49 and 1,240.84

Step by Step Solution

1. Step 1: Write the proportion equation
   2,288.78 : 3,158.49 = 1,240.84 : x
2. Step 2: Convert to fraction form
   2,288.78/3,158.49 = 1,240.84/x
3. Step 3: Cross multiply
   2,288.78x = 3,158.49 × 1,240.84
4. Step 4: Simplify right side
   2,288.78x = 3,919,172.84
5. Step 5: Solve for x
   x = 3,919,172.84/2,288.78
6. Step 6: Final answer
   x = 1,712.35