Finding the Fourth Proportional to 2,855.91, 4,284.47 and 1,212.42

Step by Step Solution

1. Step 1: Write the proportion equation
   2,855.91 : 4,284.47 = 1,212.42 : x
2. Step 2: Convert to fraction form
   2,855.91/4,284.47 = 1,212.42/x
3. Step 3: Cross multiply
   2,855.91x = 4,284.47 × 1,212.42
4. Step 4: Simplify right side
   2,855.91x = 5,194,580.15
5. Step 5: Solve for x
   x = 5,194,580.15/2,855.91
6. Step 6: Final answer
   x = 1,818.89