Finding the Fourth Proportional to 2,560.48, 3,839.10 and 916.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,560.48 : 3,839.10 = 916.72 : x
2. Step 2: Convert to fraction form
   2,560.48/3,839.10 = 916.72/x
3. Step 3: Cross multiply
   2,560.48x = 3,839.10 × 916.72
4. Step 4: Simplify right side
   2,560.48x = 3,519,379.75
5. Step 5: Solve for x
   x = 3,519,379.75/2,560.48
6. Step 6: Final answer
   x = 1,374.50