Finding the Fourth Proportional to 2,219.81, 3,063.65 and 1,288.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,219.81 : 3,063.65 = 1,288.31 : x
2. Step 2: Convert to fraction form
   2,219.81/3,063.65 = 1,288.31/x
3. Step 3: Cross multiply
   2,219.81x = 3,063.65 × 1,288.31
4. Step 4: Simplify right side
   2,219.81x = 3,946,932.15
5. Step 5: Solve for x
   x = 3,946,932.15/2,219.81
6. Step 6: Final answer
   x = 1,778.05