Finding the Fourth Proportional to 2,145.17, 3,217.89 and 847.55

Step by Step Solution

1. Step 1: Write the proportion equation
   2,145.17 : 3,217.89 = 847.55 : x
2. Step 2: Convert to fraction form
   2,145.17/3,217.89 = 847.55/x
3. Step 3: Cross multiply
   2,145.17x = 3,217.89 × 847.55
4. Step 4: Simplify right side
   2,145.17x = 2,727,306.58
5. Step 5: Solve for x
   x = 2,727,306.58/2,145.17
6. Step 6: Final answer
   x = 1,271.37