Finding the Fourth Proportional to 1,247.59, 1,722.27 and 856.63

Step by Step Solution

1. Step 1: Write the proportion equation
   1,247.59 : 1,722.27 = 856.63 : x
2. Step 2: Convert to fraction form
   1,247.59/1,722.27 = 856.63/x
3. Step 3: Cross multiply
   1,247.59x = 1,722.27 × 856.63
4. Step 4: Simplify right side
   1,247.59x = 1,475,348.15
5. Step 5: Solve for x
   x = 1,475,348.15/1,247.59
6. Step 6: Final answer
   x = 1,182.56