Finding the Fourth Proportional to 2,415.63, 3,622.78 and 855.43

Step by Step Solution

1. Step 1: Write the proportion equation
   2,415.63 : 3,622.78 = 855.43 : x
2. Step 2: Convert to fraction form
   2,415.63/3,622.78 = 855.43/x
3. Step 3: Cross multiply
   2,415.63x = 3,622.78 × 855.43
4. Step 4: Simplify right side
   2,415.63x = 3,099,023.50
5. Step 5: Solve for x
   x = 3,099,023.50/2,415.63
6. Step 6: Final answer
   x = 1,282.90