Finding the Fourth Proportional to 2,178.10, 3,005.61 and 1,338.79

Step by Step Solution

1. Step 1: Write the proportion equation
   2,178.10 : 3,005.61 = 1,338.79 : x
2. Step 2: Convert to fraction form
   2,178.10/3,005.61 = 1,338.79/x
3. Step 3: Cross multiply
   2,178.10x = 3,005.61 × 1,338.79
4. Step 4: Simplify right side
   2,178.10x = 4,023,880.61
5. Step 5: Solve for x
   x = 4,023,880.61/2,178.10
6. Step 6: Final answer
   x = 1,847.43