Finding the Fourth Proportional to 2,767.78, 4,152.12 and 820.18

Step by Step Solution

1. Step 1: Write the proportion equation
   2,767.78 : 4,152.12 = 820.18 : x
2. Step 2: Convert to fraction form
   2,767.78/4,152.12 = 820.18/x
3. Step 3: Cross multiply
   2,767.78x = 4,152.12 × 820.18
4. Step 4: Simplify right side
   2,767.78x = 3,405,485.78
5. Step 5: Solve for x
   x = 3,405,485.78/2,767.78
6. Step 6: Final answer
   x = 1,230.40