Finding the Fourth Proportional to 2,509.57, 3,463.05 and 1,390.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,509.57 : 3,463.05 = 1,390.56 : x
2. Step 2: Convert to fraction form
   2,509.57/3,463.05 = 1,390.56/x
3. Step 3: Cross multiply
   2,509.57x = 3,463.05 × 1,390.56
4. Step 4: Simplify right side
   2,509.57x = 4,815,578.81
5. Step 5: Solve for x
   x = 4,815,578.81/2,509.57
6. Step 6: Final answer
   x = 1,918.89