Finding the Fourth Proportional to 2,546.72, 3,820.16 and 815.28

Step by Step Solution

1. Step 1: Write the proportion equation
   2,546.72 : 3,820.16 = 815.28 : x
2. Step 2: Convert to fraction form
   2,546.72/3,820.16 = 815.28/x
3. Step 3: Cross multiply
   2,546.72x = 3,820.16 × 815.28
4. Step 4: Simplify right side
   2,546.72x = 3,114,500.04
5. Step 5: Solve for x
   x = 3,114,500.04/2,546.72
6. Step 6: Final answer
   x = 1,222.95