Finding the Fourth Proportional to 2,168.61, 3,251.43 and 781.22

Step by Step Solution

1. Step 1: Write the proportion equation
   2,168.61 : 3,251.43 = 781.22 : x
2. Step 2: Convert to fraction form
   2,168.61/3,251.43 = 781.22/x
3. Step 3: Cross multiply
   2,168.61x = 3,251.43 × 781.22
4. Step 4: Simplify right side
   2,168.61x = 2,540,065.89
5. Step 5: Solve for x
   x = 2,540,065.89/2,168.61
6. Step 6: Final answer
   x = 1,171.29