Finding the Fourth Proportional to 1,278.71, 1,764.15 and 806.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,278.71 : 1,764.15 = 806.48 : x
2. Step 2: Convert to fraction form
   1,278.71/1,764.15 = 806.48/x
3. Step 3: Cross multiply
   1,278.71x = 1,764.15 × 806.48
4. Step 4: Simplify right side
   1,278.71x = 1,422,751.69
5. Step 5: Solve for x
   x = 1,422,751.69/1,278.71
6. Step 6: Final answer
   x = 1,112.65