Finding the Fourth Proportional to 2,579.80, 3,870.30 and 1,099.10

Step by Step Solution

1. Step 1: Write the proportion equation
   2,579.80 : 3,870.30 = 1,099.10 : x
2. Step 2: Convert to fraction form
   2,579.80/3,870.30 = 1,099.10/x
3. Step 3: Cross multiply
   2,579.80x = 3,870.30 × 1,099.10
4. Step 4: Simplify right side
   2,579.80x = 4,253,854.34
5. Step 5: Solve for x
   x = 4,253,854.34/2,579.80
6. Step 6: Final answer
   x = 1,648.91