Finding the Fourth Proportional to 2,815.05, 3,885.86 and 2,519.81

Step by Step Solution

1. Step 1: Write the proportion equation
   2,815.05 : 3,885.86 = 2,519.81 : x
2. Step 2: Convert to fraction form
   2,815.05/3,885.86 = 2,519.81/x
3. Step 3: Cross multiply
   2,815.05x = 3,885.86 × 2,519.81
4. Step 4: Simplify right side
   2,815.05x = 9,791,615.76
5. Step 5: Solve for x
   x = 9,791,615.76/2,815.05
6. Step 6: Final answer
   x = 3,478.31