Finding the Fourth Proportional to 5,228.49, 7,215.33 and 2,870.78

Step by Step Solution

1. Step 1: Write the proportion equation
   5,228.49 : 7,215.33 = 2,870.78 : x
2. Step 2: Convert to fraction form
   5,228.49/7,215.33 = 2,870.78/x
3. Step 3: Cross multiply
   5,228.49x = 7,215.33 × 2,870.78
4. Step 4: Simplify right side
   5,228.49x = 20,713,662.01
5. Step 5: Solve for x
   x = 20,713,662.01/5,228.49
6. Step 6: Final answer
   x = 3,961.69