Finding the Fourth Proportional to 2,780.55, 4,171.61 and 1,317.69

Step by Step Solution

1. Step 1: Write the proportion equation
   2,780.55 : 4,171.61 = 1,317.69 : x
2. Step 2: Convert to fraction form
   2,780.55/4,171.61 = 1,317.69/x
3. Step 3: Cross multiply
   2,780.55x = 4,171.61 × 1,317.69
4. Step 4: Simplify right side
   2,780.55x = 5,496,892.08
5. Step 5: Solve for x
   x = 5,496,892.08/2,780.55
6. Step 6: Final answer
   x = 1,976.91