Finding the Fourth Proportional to 2,219.36, 3,062.76 and 1,288.40

Step by Step Solution

1. Step 1: Write the proportion equation
   2,219.36 : 3,062.76 = 1,288.40 : x
2. Step 2: Convert to fraction form
   2,219.36/3,062.76 = 1,288.40/x
3. Step 3: Cross multiply
   2,219.36x = 3,062.76 × 1,288.40
4. Step 4: Simplify right side
   2,219.36x = 3,946,059.98
5. Step 5: Solve for x
   x = 3,946,059.98/2,219.36
6. Step 6: Final answer
   x = 1,778.02