Finding the Fourth Proportional to 2,128.78, 2,934.18 and 1,942.90

Step by Step Solution

1. Step 1: Write the proportion equation
   2,128.78 : 2,934.18 = 1,942.90 : x
2. Step 2: Convert to fraction form
   2,128.78/2,934.18 = 1,942.90/x
3. Step 3: Cross multiply
   2,128.78x = 2,934.18 × 1,942.90
4. Step 4: Simplify right side
   2,128.78x = 5,700,818.32
5. Step 5: Solve for x
   x = 5,700,818.32/2,128.78
6. Step 6: Final answer
   x = 2,677.97