Finding the Fourth Proportional to 1,392.81, 1,919.75 and 1,112.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,392.81 : 1,919.75 = 1,112.15 : x
2. Step 2: Convert to fraction form
   1,392.81/1,919.75 = 1,112.15/x
3. Step 3: Cross multiply
   1,392.81x = 1,919.75 × 1,112.15
4. Step 4: Simplify right side
   1,392.81x = 2,135,034.80
5. Step 5: Solve for x
   x = 2,135,034.80/1,392.81
6. Step 6: Final answer
   x = 1,532.90