Finding the Fourth Proportional to 2,460.78, 3,690.29 and 816.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,460.78 : 3,690.29 = 816.89 : x
2. Step 2: Convert to fraction form
   2,460.78/3,690.29 = 816.89/x
3. Step 3: Cross multiply
   2,460.78x = 3,690.29 × 816.89
4. Step 4: Simplify right side
   2,460.78x = 3,014,544.59
5. Step 5: Solve for x
   x = 3,014,544.59/2,460.78
6. Step 6: Final answer
   x = 1,225.04