Finding the Fourth Proportional to 2,122.42, 3,180.54 and 1,861.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,122.42 : 3,180.54 = 1,861.78 : x
2. Step 2: Convert to fraction form
   2,122.42/3,180.54 = 1,861.78/x
3. Step 3: Cross multiply
   2,122.42x = 3,180.54 × 1,861.78
4. Step 4: Simplify right side
   2,122.42x = 5,921,465.76
5. Step 5: Solve for x
   x = 5,921,465.76/2,122.42
6. Step 6: Final answer
   x = 2,789.96