Finding the Fourth Proportional to 2,780.60, 4,168.18 and 1,391.86

Step by Step Solution

1. Step 1: Write the proportion equation
   2,780.60 : 4,168.18 = 1,391.86 : x
2. Step 2: Convert to fraction form
   2,780.60/4,168.18 = 1,391.86/x
3. Step 3: Cross multiply
   2,780.60x = 4,168.18 × 1,391.86
4. Step 4: Simplify right side
   2,780.60x = 5,801,523.01
5. Step 5: Solve for x
   x = 5,801,523.01/2,780.60
6. Step 6: Final answer
   x = 2,086.43