Finding the Fourth Proportional to 2,123.61, 3,178.74 and 1,340.90

Step by Step Solution

1. Step 1: Write the proportion equation
   2,123.61 : 3,178.74 = 1,340.90 : x
2. Step 2: Convert to fraction form
   2,123.61/3,178.74 = 1,340.90/x
3. Step 3: Cross multiply
   2,123.61x = 3,178.74 × 1,340.90
4. Step 4: Simplify right side
   2,123.61x = 4,262,380.41
5. Step 5: Solve for x
   x = 4,262,380.41/2,123.61
6. Step 6: Final answer
   x = 2,007.14