Finding the Fourth Proportional to 2,380.86, 3,278.79 and 2,142.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,380.86 : 3,278.79 = 2,142.78 : x
2. Step 2: Convert to fraction form
   2,380.86/3,278.79 = 2,142.78/x
3. Step 3: Cross multiply
   2,380.86x = 3,278.79 × 2,142.78
4. Step 4: Simplify right side
   2,380.86x = 7,025,725.64
5. Step 5: Solve for x
   x = 7,025,725.64/2,380.86
6. Step 6: Final answer
   x = 2,950.92