Finding the Fourth Proportional to 1,426.56, 2,139.90 and 696.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,426.56 : 2,139.90 = 696.78 : x
2. Step 2: Convert to fraction form
   1,426.56/2,139.90 = 696.78/x
3. Step 3: Cross multiply
   1,426.56x = 2,139.90 × 696.78
4. Step 4: Simplify right side
   1,426.56x = 1,491,039.52
5. Step 5: Solve for x
   x = 1,491,039.52/1,426.56
6. Step 6: Final answer
   x = 1,045.20