Finding the Fourth Proportional to 2,158.39, 2,978.61 and 1,226.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,158.39 : 2,978.61 = 1,226.89 : x
2. Step 2: Convert to fraction form
   2,158.39/2,978.61 = 1,226.89/x
3. Step 3: Cross multiply
   2,158.39x = 2,978.61 × 1,226.89
4. Step 4: Simplify right side
   2,158.39x = 3,654,420.69
5. Step 5: Solve for x
   x = 3,654,420.69/2,158.39
6. Step 6: Final answer
   x = 1,693.12