Finding the Fourth Proportional to 1,579.43, 2,180.05 and 916.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,579.43 : 2,180.05 = 916.50 : x
2. Step 2: Convert to fraction form
   1,579.43/2,180.05 = 916.50/x
3. Step 3: Cross multiply
   1,579.43x = 2,180.05 × 916.50
4. Step 4: Simplify right side
   1,579.43x = 1,998,018.69
5. Step 5: Solve for x
   x = 1,998,018.69/1,579.43
6. Step 6: Final answer
   x = 1,265.02