Finding the Fourth Proportional to 2,086.50, 3,128.54 and 916.46

Step by Step Solution

1. Step 1: Write the proportion equation
   2,086.50 : 3,128.54 = 916.46 : x
2. Step 2: Convert to fraction form
   2,086.50/3,128.54 = 916.46/x
3. Step 3: Cross multiply
   2,086.50x = 3,128.54 × 916.46
4. Step 4: Simplify right side
   2,086.50x = 2,867,161.54
5. Step 5: Solve for x
   x = 2,867,161.54/2,086.50
6. Step 6: Final answer
   x = 1,374.15