Finding the Fourth Proportional to 1,272.28, 1,764.72 and 1,238.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,272.28 : 1,764.72 = 1,238.56 : x
2. Step 2: Convert to fraction form
   1,272.28/1,764.72 = 1,238.56/x
3. Step 3: Cross multiply
   1,272.28x = 1,764.72 × 1,238.56
4. Step 4: Simplify right side
   1,272.28x = 2,185,711.60
5. Step 5: Solve for x
   x = 2,185,711.60/1,272.28
6. Step 6: Final answer
   x = 1,717.95