Finding the Fourth Proportional to 2,158.62, 2,978.79 and 1,227.42

Step by Step Solution

1. Step 1: Write the proportion equation
   2,158.62 : 2,978.79 = 1,227.42 : x
2. Step 2: Convert to fraction form
   2,158.62/2,978.79 = 1,227.42/x
3. Step 3: Cross multiply
   2,158.62x = 2,978.79 × 1,227.42
4. Step 4: Simplify right side
   2,158.62x = 3,656,226.42
5. Step 5: Solve for x
   x = 3,656,226.42/2,158.62
6. Step 6: Final answer
   x = 1,693.78