Finding the Fourth Proportional to 1,215.91, 1,678.51 and 796.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,215.91 : 1,678.51 = 796.28 : x
2. Step 2: Convert to fraction form
   1,215.91/1,678.51 = 796.28/x
3. Step 3: Cross multiply
   1,215.91x = 1,678.51 × 796.28
4. Step 4: Simplify right side
   1,215.91x = 1,336,559.69
5. Step 5: Solve for x
   x = 1,336,559.69/1,215.91
6. Step 6: Final answer
   x = 1,099.23