Finding the Fourth Proportional to 2,800.72, 3,869.94 and 2,215.90

Step by Step Solution

1. Step 1: Write the proportion equation
   2,800.72 : 3,869.94 = 2,215.90 : x
2. Step 2: Convert to fraction form
   2,800.72/3,869.94 = 2,215.90/x
3. Step 3: Cross multiply
   2,800.72x = 3,869.94 × 2,215.90
4. Step 4: Simplify right side
   2,800.72x = 8,575,400.05
5. Step 5: Solve for x
   x = 8,575,400.05/2,800.72
6. Step 6: Final answer
   x = 3,061.86