Finding the Fourth Proportional to 1,391.56, 1,919.82 and 1,036.87

Step by Step Solution

1. Step 1: Write the proportion equation
   1,391.56 : 1,919.82 = 1,036.87 : x
2. Step 2: Convert to fraction form
   1,391.56/1,919.82 = 1,036.87/x
3. Step 3: Cross multiply
   1,391.56x = 1,919.82 × 1,036.87
4. Step 4: Simplify right side
   1,391.56x = 1,990,594.16
5. Step 5: Solve for x
   x = 1,990,594.16/1,391.56
6. Step 6: Final answer
   x = 1,430.48