Finding the Fourth Proportional to 2,178.40, 3,267.72 and 1,815.76

Step by Step Solution

1. Step 1: Write the proportion equation
   2,178.40 : 3,267.72 = 1,815.76 : x
2. Step 2: Convert to fraction form
   2,178.40/3,267.72 = 1,815.76/x
3. Step 3: Cross multiply
   2,178.40x = 3,267.72 × 1,815.76
4. Step 4: Simplify right side
   2,178.40x = 5,933,395.27
5. Step 5: Solve for x
   x = 5,933,395.27/2,178.40
6. Step 6: Final answer
   x = 2,723.74